Read all of Dan Harrington's books; Harrington on Hold'em (vol 1-3).
If you don't have time to do that here are my tips:
In most tournaments there are going to be a lot of fish. Don't be intimidated. There are plenty of other players who are inexperienced just like you.
For the most part a tournament is a marathon, not a sprint. You don't need to act desperate in the first few blind levels. Generally you will have a pretty big stack compared to the blinds (a high 'M'). You don't have to get crazy trying to double up. Be prepared to sit back, relax and fold. Play premium hands. You are not Gus Hansen nor are you Daniel Negreanu. You are not good enough to play 75% of hands and get away from tricky situations later on.
Do not risk all your chips unless you really have to. Remember when you see tournaments on TV all that all in action is caused by huge blinds and antes forcing players to get a little crazy. The early stages of a tournament are not like that.
If in doubt fold.
Consider wearing sunglasses to hide your eyes, but only if you are completely comfortable with them. Don't buy a set of dark Oakleys and then get into trouble because you cannot see the board cards. I personally like Tag Heuer as they make very light lenses that don't obscure your vision. Don't wear red or brown colored lenses or the red cards will be hard to see.
Always put a chip on your hole cards so that the dealer does not accidentally muck them.
Don't wear an iPod. You will miss some of what is going on. Only top pros should ever wear an iPod.
Look at your cards when it is your turn to act. Not before. Watch all the action before it gets to you. Don't call a raise and reraise unless you have a monster, in which case you should probably be raising.
If your hand is only good enough to call, maybe you should fold. Don't look for excuses to play weak hands.
Unless you have an amazing hand, do not play in the first three positions. Play tight in early position, loosen up in late position.
That's all I have for now. Good luck, it's a lot of fun.