Do you have a bubble level on your sight? if not get one...visualize your arm and hand as a post holding yout bow in position, it should not move much, rotate, flex, whatever. If you are twisting your bow at the shot it probably means some target panic. Some bow designs also are made to help this by distributing as much mass as far from the handle as possible (toward the limbs) this resists a slight impulse to rotate, but you still need good form.