Set-up: Make sure your environment is safe to perform this movement in. A wall or net in a suitable facility or outdoors with no one around are both fine options.
Movement: Grasp a medicine ball with both hands, and rapidly descend into a quarter squat. As you descend, bring your arms and the ball from overhead to in front of your body. At the bottom of the movement, explode upwards swinging your arms overhead and backwards. Release the medicine ball at the top of the movement sending it up and back.