TheKidd's Team Fortress 2 Guide of Awesome.

Scout

1. When falling from great heights, hit jump again just before the ground to double jump, and avoid fall damage.
2. Even when being attacked, you can still sneak by the enemy's defensive line. Sometimes they feel you aren't worth it, or are just too fast to catch. This is perfect for attacking from behind or sniping sentries.
3. If behind front lines, find a corner near a cap, or just out of the way, and tell the team what's happening. If they're attacking cap 3, and you're behind cap 2, watch what's going on. If your team loses cap 3, and begins defending cap 4, you're usefulness for your location has been lost, and you need to get back out there. If they secured Cap 3, pounce on cap 2 before the enemy team has a chance to setup.
4. Sometimes the scout can best be used to delay the enemy team's capture. Say you're playing a Soldier defending on cp_gravelpit, and the attacking team just started capping Point A with x5, right as you die. You notice that most of your team is also dead. Consider spawning as a scout and running a beeline to Cap A. Jump on the cap, and avoid enemy fire as long as possible. As long as you're standing on the cap, they can't take it from your team. This will give the rest of your team a chance to respawn and take the rest of them out.
5. You should NOT use teleporters. Leave them for the slower members of your team. In most cases, it would actually take longer to wait for the teleporter to charge than to just run to your objective.
6. If you can fake out a demo into detonating his stickybombs, you can usually get a headstart on capping while the rest of your team shows up, ensuring that the stickybombs won't be hurting them.

Engineer

1. When your buildings are sapped and you're too far away to save them, consider zapping them. It doesn't give them the points.
2. Teleporters should never been seen by the enemy unless you got a beaucoup defense around them. Behind walls, on top of buildings.
3. If you have the time, do NOT just leave your buildings to build themselves. Hit them with your spanner, they will build faster!
4. You can press mouse2 to rotate a building 90 degrees.
5. Always Always move your teleporter up if your team just captured a new point (for example, a map like cp_granary and cp_well). If the teleporter entrance is behind their new spawning area, it does them no good.
6. From the spawn, the first thing you should be is a teleporter entrance just outside the spawn door. Then go back inside, resupply, and then go build the rest of your contraptions.
7. Keep your back to the wall so spies can't instantly kill you and have their way with your sentry and dispenser.
8. Teamwork is extremely important when playing engineer. If your teams defenses have fallen, including everyone's sentry gun, all the engineers should focus on building ONE sentry gun and ONE dispenser, and upgrade it as soon as possible. 3 level one sentry guns will do very little against the onslaught that eliminated your last defense. Everyone should band together to get that first sentry gun up.
9. Be aware that while your dispenser is being built, it can be used as a stepladder to reach new heights, giving entirely new sentry positions.
10. On timed-gate-opening maps, you have to be incredibly fast. Get the teleporter entrance up, get the sentry up, get the dispenser up, all before the gates open (if possible). You have to be methodical, and have to have it down to a science. You should almost be bored with how easy it is to get everything up before you even see an enemy.
11. For other sentry positions on other maps, click on this link.

Pyro

1. You are the spy finder. Everyone expects you to find the spies, so check for them constantly.
2. As a defender, you can quickly clear the cap. That "x5" multiplier for the attacking team can quickly become nothing after igniting their team.
3. Be conscientious about who you're attacking. Igniting a scout and running off will surely kill him, but igniting a heavy and running will rarely kill him. He gets the most attention from the medics, and has a ton of health. You will have to consider how big a threat he poses to your team. Is he worth losing your own life to kill? If you see an enemy medic, you should almost always try to ignite him.

Spy

1. Avoid using the teleporters. It gives you a trail effect for several long seconds, and can easily give away your true team colors.
2. Changing disguise while cloaked envelopes you in smoke and light. Be conscience of this when you do so, and do it out of sight.
3. When disguised as a class that should be faster (like a scout, or a medic), you do NOT run faster. But when disguised as a slower class (like a heavy, or a soldier), you DO run slower.
4. Always disguise yourself for the area you're going to be attacking. If you're trying to take out the heavy's on the front lines, disguise as a demoman. If you're going to take out the sentry guns, disguise as an engineer.
5. Saps can kill a turret even when an engineer is trying to get rid of them. Just keep the sentry in between you and the engineer and continue planting saps on it until it explodes.
6. No matter what weapon the spy is wielding, he appears to be using the default weapon of the kit he's impersonating.
7. If you clear out a cap, and your teammate scout comes up to start capping it, for the love of god, undisguise yourself and help him out. Make sure no one from the enemy team is coming, and turn that x2 to a x3. It will make the difference. If the enemy team comes back to make a push at that same command point, merely cloak yourself back, and run off. Cloaked/disguised spies, can NOT capture points.
8. I think the best thing to do though is to act the part you're playing. Don't just dress up as the enemy, ACT like the enemy. And use your cloak for getting into believable positions.

Soldier

1. Don't be afraid to rocketjump in order to get somewhere quick. Sometimes it's more important that you get somewhere quickly than with a lot of health.
2. At a map that has setup time, do the entire team and damage yourself. A nearby medic will heal you up, and the more health they have to heal, the faster their ubercharge gets charged up, and your team can explode out of the gate with an impenetrable wave of doom. As soon as you spawn, hit the "call medic" button, so that a medic will know how serious you are about shit going down, and he will now be able to easily find you.
3. However, do NOT just rocket jump all over the air. Stay near the resupply cabinet, and just fire straight against a wall. It will heal faster and you wont' have to reload.
4. Also, do not do this at the expense of staying in the spawn a 5-10 seconds after the gate opens. Your team needs you to be out there with them. If the medic's charge is only at 80%, that's enough. He should be able to get that last 20% easily after the gates open.
5. Sometimes, it will be up to you to destroy sentry guns. At long ranges, they can't detect you, but you can easily spot them. 3-4 rockets will sometimes be plenty.

Demoman

1. Grenades do not automatically detonate after their first bounce off the ground or wall. They also do not do a great amount of damage, so be prepared to shoot many of them if your target is around a wall.
2. Stickybombs are perfect for shooting at long ranges, and behind cover. If your team is having trouble with a sentry across the field, lob a few sticky's over a wall and detonate them with ease.
3. Make an attempt to hide stickybombs placed around a doorway. Not only will it be obvious you are there, but enemies might try and shoot them off.
4. Conversely, it might be worth it to leave them there. It will deter others from taking that path, and force them elsewhere.
5. If your team is pushed back, place your stickybombs on the control point. They become a fail-safe for when the enemy team attempts to cap, and you're far away.

Heavy Weapons Guy

1. When coming around a corner, alt-fire to have your gun spinning and ready to fire when you first see an enemy.
2. It's easy to go through ammo quickly, so pickup replacement ammo from dead bodies whose weapons are still laying around. (especially if your medic has the ubercharged ready to go, and you're stuck at 50 shells. Find more ammo, or it will probably be a wasted ubercharge)
3. At best, Sascha is decent at long range, so keep your targets as close as possible to ensure accuracy.
4. Keep track of who's healing you and how good a job they're doing. Sometimes assuming a medic will go with you into the heat of battle is a mistake, as the bad medics will leave you to your own.
5. If your medic has an ubercharge up, attempt to tell him you're ready to use it. through voice chat, or the prepared voice actions that TF2 has programmed.

Medic

1. You should rarely ever have to shoot the needlegun. Your healing gun should be out almost at all times. Your finger should hurt from all the pressing down of the "fire" button that you do.
2. When you first spawn at a delayed start map (like dustbowl), you should immediately find a soldier who has called out for a medic. He will be your buddy for the next 60 seconds as you try and heal him. But don't be scared to leave when the countdown reaches 10 or 5 seconds and your uber isn't ready. You need to be with the frontlines, healing them as well. You will be able to heal plenty to get your uber up then.
3. Consider healing other targets than just heavies. Pyros and sometimes spies can make for fun times.
4. Don't heal spies on your team that are cloaked. They don't want your help if they don't ask for it, and you will expose them to the other team.

Sniper

1. Stay as far back as possible, but still be able to see the enemy's advance. You should never be in the thick of things.
2. Always have your back to the wall. Usually when a spy slips through your defenses, the first person they take out is the sniper, since you're all alone.
3. Stay zoomed in for long periods of time, and your shot will do more damage, per the meter on the right side of your scope.
4. When zoomed in on an enemy engineer's setup, take out the engineer first. Not only will you now be able to take out the other buildings with ease, if you get taken out shortly after, your team will be able to destroy them without having to deal with the engineer.

Well

I have nothing to say about Well except that it's awesome.

Gravelpit

The main note to make here is that before point C can be captured by the attacking team, they must first capture points A and B. That isn't to say that point C isn't worth visiting in between attacking B and A. A quick visit can dispel any teleports or sentries that you come across.

For the attacking team, this means that sometimes it might be a better option to let A or B fall early, in hopes of having a tighter defense on the other point. A split defense between both points can mean a quick fall if the attacking team is coordinated enough to put all their force into attacking one point.

Granary

I have nothing to say about Granary except that it's awesome.

Dustbowl

Placements on Dustbowl. These images convey prime spots for certain objects and people to be placed while defending the command points on dustbowl (although it's worth noting that many of these spots work for the attackers as well, but might require slightly differing positions, and directions). They are not perfect, as no spot in TF2 seems to be perfect for anything. But they are preferable over others, and have proven to be effective.

Key

S	Sentry Gun, Dispenser, Engineer
D	Demoman
H	Heavy Weapons Guy
N	Sniper
P	Pyro

Command Point 1

Command Point 2

Command Point 3

Technical Questions

Q: What are the minimum specs for TF2?
A:

• 1.7 GHz Pentium 4
• 512 MB system RAM
• DirectX 8 compatible video card

Q: TF2 was working, but now it's not. I played it just fine an hour ago/on the server right before it crashed/last night/at your mom's house. What's the deal?
A: The basic rule of thumb for having random problems with TF2 (or most steam games) randomly deciding not to work correctly, or to not connect to a server, is to restart steam, and log out and log in (these are SEPARATE actions. One requires you to quit steam, while the other requires that you go to File -> change user in steam). Do both, and you have your bases covered. Then, if that doesn't work, try one of the methods listed below.

Q: What does it mean when it "can't verify your STEAM userid ticket"?
A: logout of steam, then log back in.

Q: What does it mean when I'm having connection with the VAC server or something about 2 min into a game.
A: Quit steam and restart fixed it (credit: Patch-e)

Q: Game crashes directly to desktop before getting to the menu system.
A: Run the game in windowed mode. Right click on "Team Fortress 2" in steam, go to properties, then click on "set launch options" and add "-windowed " to the box. This shouldn't happen in recent TF2 versions.

Q: Game crashes with sound loop endlessly. How do I fix this?
A: Try running in windowed mode.
A: Go into dxdiag and turn audio hardware acceleration to "none". Do the same for sound in the control panel for hardware acceleration. (credit: hl2world.com)

Q: Is there anyway to speed up loading in TF2? I have 2 gigs of ram, do I need more?
A: For the initial load where it loads up a map for the main menu, to stop that, add +map none in the command line (right-click game in Steam, choose Properties, go to Set Launch Options, put in +map none.)
A: adding -console to the shortcut makes the menu load faster (cuz it won't load the map as a background if console is up)
A: -novid in the launch options will autoskip the valve video

Gameplay Questions

Q: Why do I keep dying so quickly?
A: Because you suck at this game. But so does everyone else, so it's okay.

Q: What factors do respawn time depend on?
A: They Depend on how well your team is doing. The better your team is doing (more command points you have), the less your respawn time. The max your respawn time can be is 25 seconds.

Q: When I switch classes, does it respawn me instantly or does it wait until I'm dead? A few times I respawned and decided to change and respawned again instantly. I was in the initial room though.
A: There is an option to do either. Options -> Multiplayer -> Advanced will let you select whether you die instantly when you select a new class, or whether it will wait till you die of your own accord.

Q: What do the sappers do?
A: Sappers are devices that spies have that allow them to take out enemy buildings (Dispensers, Teleporters, Sentry guns, all built by engineers). They attach to the building and then proceed to damage them.

Q: Is there a way to defuse sappers as an engineer?
A: If you hit them with your wrench (possibly multiple times), it will remove the zapper.

Q: Is there going to be a huge difference between what we see in the beta and the full release?
A: All indications are that there probably won't be a difference.

Q: How do I get a critical hit on someone?
A: Critical Hits happen when you string together a series of quick kills, or when you get a headshot with the sniper. (credit: helvetica)

Q: As an engineer, when I hit "4" to build something, sometimes it's an accident and I don't want to build anything. But there is no key bound to exit that menu, and I don't see what to set in the keyboard bindings GUI. Help?
A: Pressing 'Q' will exit the build. (credit TreMetal and Busdriver)

Q: How long do the demoman's sticky bombs last before they blow up automatically?
A: As long as you last. (credit: krillin)

Q: What class is fastest/slowest?
A: Speeds of classes, fastest to slowest: Scout > Medic > Pyro, Sniper, Spy, Engineer > Demoman > Soldier > Heavy. (credit helvetica)

Steam Questions

Q: Is there some trick to getting the console to come down? I tried hitting `/~ and it doesn't seem to work.
A: In game, press ESC, go to Options, select the "enable developer console" option, and it will then work when you press "`/~"

Q: How do I change my name:
A: To change your name, you have to change your Steam friends name. Shift + tab brings it up in-game. (Credit: Helvetica)

Q: When will steam community allow more than 50 people in a chatroom?
A: That is currently being worked on.

Q: Is the game worth it?
A: Yes.