[otnemem]

If he just calls the flop three-bet and checks the turn, I bet the turn and try to get a free showdown. If he just calls the three-bet and bets out on the turn, I fold. If he just calls the three-bet and check raises the turn, I fold (screams set). If he caps the flop, I call and fold the turn if I don't improve.

EDIT: I pretty much completely disagree with everyone else's advice here, especially the argument for raising a limped pot with a very marginal suited one-gapper. This isn't six-max.