[imported_The Vibesman]

Gotta mix it up, but I think the simplest, easiest solution is to just call down the whole way. This keeps you from spewing chips when you are behind and keeps you from getting bluffed out when you are ahead by an aggro opponent, say the type that will re-raise the flop against a perceived steal defense.

Another concept to think about, though, is whether you want your opponent to fold or not, and whether he will fold. Say SB raises, you call w/ 44 and the flop comes A82 rainbow. I think if you know SB will raise plenty of hands without an ace, that a flop raise may be in order. It's possible you could get him to fold a 6-outer here or on the turn. If you are played back at you can safely fold.

There's a lot of other things to think about, I hope this can get you started.