It depends on how many people call and what turn you are on betting. If you're early, I'd just call or raise 1x. If you're later in turn and there's a lot of people that are playing, i'd raise 3x+, if there's just one person in it, I'd call and try to get him to raise you. Then on the flop, if a flush draw is available (ie, 2 cards are suited) I'd go all in just in case. The main thing is, just don't scare the money away too early, but make them make a call before their hand is revealed. I'm no pro, but I've misplayed them enough to know that it sucks to rake a small pot off AA