Learning how to play in different positions has probably helped my game more than anything else. When I started playing I would play AK the same whether on the button or UTG.

Also, I've learned that when you are going to play a hand out of position, i.e. from the blinds, you need to get as much information about your opponent's hand as possible. You will be acting without information for the rest of the hand, so the time to get information is preflop. Best way to do this is reraise. If he raised before the flop with a medium-strong hand to take down the blinds, he'll either fold or call and be cautious with his future bets since you've declared that you have a strong holding. If he reraises, you know he's probably got it. In this way you can force your opponent to define his hand preflop so that this can inform your postflop play. Of course, if you can't justify raising with your hand, it's probably not worth playing OOP.

In this context I'm speaking about situations when I have a relatively strong holding. I personally very rarely "resteal" with weak hands as I don't feel that my reading abilities are good enough to make this a profitable play. I hope to do this more as my experience increases.