Beginner heads up question.

Hey guys, Im semi-new to poker and have a quick question for you. I play a lot of poker on full tilt poker, facebook poker, and on xbox live. Iv never played with real money, other then at family games because im only 18.
I have been readin as much about no limit hold em and trying to study as much as I can and I still am confused in one area of the game specificaly.... Heads up play.
Ill play in a tournament style game and it almost always comes down to just me and another guy because ill play relatively tight and let the other players bust each other out early on. Most of the time when it boils down to heads up play the othe guy will have alot more chips then me just because he played a little looser but this is not always the case.. So I have 2 main questions:
1. What cards should I play preflop in headsup? I get used to folding shitty hands preflop but i dont want to just keep letting the villian steal my blind time after time. I realize i have to play looser but what hands should I fold right away and what hands should I play in heads up?
2. Should I play heads up differently when the villian has a good chip lead on me? Tighter, but then Ill just keep giving up my blinds and lose a little at a time or looser and risk losing it all?

The questions are some what similar but as you can tell I need advice and am pretty new, and heads up brings me alot of trouble. Thanks guys!

1. You got to get used to your opponent. Learn his game see how he plays, does he play loose or tight. If he's calling with nearly everything or raising then do the same thing. Don't wait for him to do something, attack him back. If he raises your raise and you feel he's bluffing, do a 4 bet. You can't fold, fold and fold some more. You have to bet and be aggressive. Be very unpredictable, start raising with hands like 27 and wait and act like your making a big decision with AA. This will through your opponent off beat and he will not know what your doing. Remember don't play your cards, play your opponent.

In heads up it is not too important the cards u are getting, those in ur opponent will be many times worse.

Just play with him, look at his bets, think if they are true ones or not, play hard, be tought dont let him steal u.

This is a nonsense, but I must say it, ur villain isnt taking good cards always, and he isnt always hitting the flop. Dont think that. And try making he think u are hitting more times than u are really doing

It sounds like you are playing STTs. So, SnG strategy by Colin Moshman would be a great place to start. It has a good chapter on heads up play as well, but will help you get heads up with a bigger stack.

*****And I am wondering what your volume is, since you state you are getting heads up regularly, which is not going to be sustainable over a large amount of games. If you "almost always" make at least second place, this is pretty incredible results. SO how many games and what format are we talking about here?

As far as what hands to play HU, Amroth made some good points. And position and bet sizing of villain are very important, among other things. If you are first to act, you should be raising (or, depending on stack sizes, going all in) with a lot of hands that may surprize you. It is very important to show strength and be aggressive. 2 face cards, any suited A, A9o+, SC 5 6 upwards, even stuff like Q9, K9 can be great hands to put the pressure on with. If you are not raising or re raising with these hands at least sometimes you are way to tight for HU play. As well as re-raising with similar when you put your opponent on a steal. And so on, there is so much to think about. Noting how your opponent plays is so important, stack sizes, blind level blah, blah, blah.......

It is hard to say generally, since it will always be dependent on your present situation, but when you get HU you CAN NOT wait for a premium hand. Use aggression and presure your opponent.

Thank you so much everyone! Your tips have helped tremendously! I just won a sit and go and when it came down to heads up i felt much more comfortable. He was a very good player, switched it up often so it was very hard to pin down his style making it very frusterating at times. So it just shows he really knew what he was doing haha.
At first i was being far to tight so he would fold whenever id play a hand and i thought about what you guys said and i knew i had to change it up. I started getting way more aggressive re raising and making him fold. Once i stopped backing down things started improving vastly. I tried to trap him a few times by slow playing and he kept folding because he realized my strategy, but finally i hit an aggressive winning streak and got a AQ and ended up slow playing it, letting him bet and re raise, then i baited him into going all in and pinned him with a full house! So thank you guys so much! I know i have so much to learn! Im sure you all remember when you were newer to the game and how overwhelming the strategy and terminology was to you! Haha Thanks guys!