Probably need a bit more information for specific advice. For example:
- What general style are you playing?
- When you make the money / final table, is it as one of the short stacks, or one of the big stacks?
- What size tournaments are you playing? 50 person, 500 person, ?
A very, very
general strategy for MTTs would be:
- Play tight early, let the other players knock each other out and thin the field for you. Don't bother with marginal hands and bluffs unless you've got a really good read.
- Loosen up and play aggressively around the time of the bubble: there'll invariably be people who just want to limp into the money, and don't want to take risks. You'll want to be stealing their chips.
- Tighten up briefly after the bubble: the same people who've been folding aces just to limp into the money will now be looking to either double up or drop out
- The above process can sometimes repeat when the final table bubble arrives
Final tables are almost a thing unto themselves. By this stage you should have some decent reads on the other players at the table, play accordingly, steal where you can, etc. Just try not to get involved in pots with the big stacks unless you're sure of your hand, because they can destroy you if you make just one mistake.
There's a whole bunch of books that've been written on this very subject - I'm in the middle of Harrington on Hold 'em at the moment and it's proving to be very educational. There's all sorts of useful stuff in the http://www.cardschat.com/poker-strategy.php