The mechanics for a curveball aren't much different from any other pitch. It's the grip, and what you do when you release the pitch, that is a change.
- Wind up normally, and throw with the same speed as your fastball. Don't slow your arm down. The ball will slow down naturally when it encounters wind resistance with the curveball spin. The proper angle of your hand is important. Picture yourself doing the "tomahawk chop" with the baseball in your hand. For right-handed throwers, the palm of your hand should be facing first base as the ball goes over your head. For left-handers, reverse that. The palm of your hand should be facing third base.