Cut out a quarter-size semicircle around the air valve of the ball. Pull back the rubber valve area and fill the ball with sand (shake along the way so that it settles).
A completely sand-filled basketball weighs around 22 pounds. If you want a lighter ball, use a scale and stuff an old T-shirt or towel in the ball to take up space without adding weight. Do this as you fill the ball with sand so the fabric is spread evenly throughout.
Once filled to desired weight, push the tab back into place. Cover the hole with Duct tape.
To improve the grip and contour of the ball, cover the ball with an old towel or T-shirt. Then, using duct tape, tightly wrap the entire ball until no fabric shows through.
Work It! Squat to overhead press: Hold ball at chest level. Squat down, then explode up extending arms up and pressing ball overhead. Repeat. If advanced, add an overhead release and catch the ball.