Lie on your back with a pillow supporting your head if required.
Fully bend your elbow on your affected arm.
Use your other arm to lift your affected arm up, keeping your elbow fully bent.
Once your arm is at 90 degrees with your body, straighten your elbow.
Your arm should now be fully vertical.
Keeping the assistance of your supporting arm, begin making small clockwise circles with your arm.
Change direction and make small anti-clockwise circles.
Gradually increase the size of the circles as far as you are able to go.