I think the most important thing in HU is the button. I will raise on the button with any face card and mid suited cards. Try to stay away from calling raises off the button, you are at a huge disadvantage postflop. I'm not a big fan of raising off the button unless you have a really good hand.

HU is all about playing your opponent and setting him up for the destack. If he is really aggressive and bets at everything check raise him a lot. If he moves AI everytime you limp preflop to him, try limping to him with your monsters, and call his AI when he moves. If he's very passive, just bluff at him a lot and back down when he plays back. Raise this player a lot preflop. Remember high card wins HU. A2 beats KQ 60% of the time, but also remember that A2 is easily dominated so don't be too quick to make moves with a hand like this. My favorite hands to raise an opponent AI with are any suited Aces, any ace offsuit down to A8 and suited connectors or 1 gap connectors. That's about all the strategy I have for you. Good luck to you.