If you have a form to clamp your bow to it and use dry heat without oil but only on the belly. When you get the crooks worked out(clamps and wedges) and while it is still on the form, "toast" the belly with your heat gun. Char it until the wood is brown in color. After you do this, let it rest a week to rehydrate before you remove it from the form.
When you adjust the bends, over correct them by a little because the wood will come back some when released.