Place the elastic loops over the middle finger and little finger of the throwing hand, with the tension strap facing the palm of the hand. Bend the wrist forward and place the wrist strap on the arm below the wrist, so that tension developed from the tension strap keeps the wrist forward comfortably. When properly placed on the hand and wrist, the Curveball Trainer will keep the wrist cocked toward the body. This is the position the hand needs to be in when the throw is completed in order to develop the proper rotation for a curve ball.

Attach the Zip Curveball Trainer to the fingers as shown in C-1 with the wrist cocked fully forward toward the body. Grip the ball as shown in C-1 with four laces in the direction of the desired rotation, with the middle finger firmly gripping the ball, and the index finger lightly touching the ball as in C-2. (The hand is turned in a position similar to that of holding a cup or glass of water.) The proper rotation comes off the middle finger.

In delivering the ball, bring the ball to the top of your delivery motion as shown, bringing your arm down across the body and releasing it at the center of the body off the middle finger. The ball will "roll" off the top of the index finger. You will be amazed at how easily the curveball develops once you get hand, arm, and wrist coordinated for the proper rotation on the ball when it is thrown. Once you have developed a curve, hang on to your Zip Curveball Trainer. When your curveball starts to get a little weak, use the Trainer again. It will quickly strengthen the arm, wrist, and finger coordination for throwing a curve. A useful exercise for some pitchers is to hold the baseball, with the hand cocked, like you are throwing a curve, and snap your fingers. With some practice, you will be able to spin the ball in the air when your fingers snap.