Attach a resistance band to a fixed point at about chest height.
Step one hand through the band and walk back until you feel gentle traction pulling your arm out of the shoulder joint.
With the arm straight, move the shoulder through full circumduction: reach forward, lift the shoulder up to the ear, pull it back, depress it down, and reach forward again.
Reverse direction: depress, pull back, lift up, and reach forward.
Repeat 5-10 circles in each direction, keeping the arm as straight as possible — only the shoulder girdle moves.
Next, with the joint still under traction, place the shoulder in different positions (protracted, retracted, elevated, depressed) and draw figure-of-eights or small circles with the arm.
Explore all possible shoulder positions. Increase tension by stepping further from the anchor point.
Repeat on the other arm.