[header] How to prevent shoulder dislocation [title] Press inward and outward with your arm to strengthen your rotator cuff. [step] With your elbow at a 90-degree angle, your upper arm against your body, and your other hand directly in front of you, press inward against your other hand. Hold for 5 seconds. 
With your arm in the same 90-degree angle, press outward against a wall or other solid surface for 5 seconds. Do this 20 times apiece, then repeat with the other arm.