a) Avoid repetitive over headed activities.
b) Avoid prolonged, sustained overhead activity.
c) Warm up slowly if you are planning to do activities that require shoulder motion (e.g. golf, tennis, weight lifting, etc)
d) If an exercise or activity causes shoulder pain, stop.
e) If planning to increase frequency, duration, intensity or weight with overhead activity, do so in slow increments.
f) Keep your muscles of your shoulder (i.e. rotator cuff and scapular stabilizers) strong and healthy with low-weight exercises