Start with the ball low in a squat position.
In a single movement stand up and swing the ball overhead. Do not clean and press.
As you reach the apex jump letting the ball pull you up.
Begin the pulling the ball back down to the ground before you land. Bend the knees to land and keep pulling the ball down to the ground.
Slam it hard! Do not just let gravity do the work.
Do it without the jump when first teaching people the slam movement. Video.