HOW: Grab onto a doorway with the arm that you want to stretch. Then tighten your shoulder blades to lock your shoulder blades from move. Slowly step away from the door and slightly turn away from it until you feel the stretch.
FEEL: You should feel a deep stretch in the back of your shoulder.
COMPENSATION: The most important part of this stretch is to squeeze your should blade. If you do not squeeze your shoulder blade, you will feel the stretch in a completely different area!