HOW: Lie on your side with support for your head from a pillow or opposite arm. Bend the top elbow to about 90 degrees. From here, bring your arm up overhead as high as you can while maintaining the bent elbow. Your hand should be going just next to your head as you bring it up.
FEEL: You should feel your shoulder muscles working.
COMPENSATION: Keep your elbow bent as you bring it up. Don’t twist your back, maintain the side lying position. Don’t shrug your shoulder