Use a heat gun, not a torch or stove. Don't heat the entire blade because it'll weaken the epoxy and overall strength of the blade. Only heat the section where you're trying to put a knuckle in the curve or the upper part if you're trying to open the toe curve. Bend it either with a vise or under a door. If you heat enough, you can use a pair of heavy duty gloves to shape it.
Practice on some old sticks or blades first.
Don't get too ridiculous with the curve or you won't be able to stick handle or backhand.