Lie on your stomach and rest your forehead on your hand or a towel roll.
If advised, place a pillow under your chest.
Put a folded towel under your shoulder and upper arm so that your elbow is level or slightly lower than your shoulder.
Move your arm away from your body until your elbow is almost even with your shoulder.
Let your forearm hang over the edge of the surface.
Rotate your shoulder by gently lifting your fingers, wrist, then forearm toward the ceiling.
Use minimal effort and do not lift your upper arm off the towel.
Once you have gone as far as you can EASILY go, let your forearm and hand return to the starting position and repeat.
