Challenging your shoulders with simple, low risk movements at numerous angles is a fantastic way to start adding strength and awareness, and to keep injuries at bay.
Set up a TRX or gymnastics rings at about chest height.
Grip the handles and lean back to an angle you can comfortably support yourself.
Start to rotate your shoulders in small circles, 3-5 forwards then 3-5 backwards.
If it feels okay then start to make larger circles and really get a feel of all of the muscles working together to support the shoulder.
To make the movement more challenging, you can walk your feet further out or even elevate your feet to increase the load. Build up over a few sessions to being able to do 3 sets of 10 reps forwards and backwards.