1. Work in your bodies entire Range Of Motion (ROM)
2. Do flexibility exercises to increase your ROM
3. Perform exercises that target fast and slow twitch muscle fibers in the entire ROM
4. Perform targeted exercises, while progressively increasing resistance, to build stability and power.
It is very important to do movements that build the posterior deltoid, and perform rowing movement to focus on the scapular retraction action, as well as a 'reverse shrug' to focus on scapular depression.
Very few, none to my knowledge, other tools or forms of exercise will give you the combined benefits and exercises, as described above, simultaneously while increasing and improving your:
If you have an injury always consult a health professional first.