I've pulled or hurt my rotator cup. I've had a cortisone shot. It helped for a bit. Now it hurts again. What can I do for relief? What helps? Ty

Depends on the level of damage, the shot only helps for a while, is not a cure. Have they talked about surgery ? Have you had physcial theropy?

Rotator cuff is the correct term.
Your doctor should tell you when you can start strengthening exercises, which are very specific.
You might need a series of small amounts of cortisone for a while - obviously not too much. At home, keep warm and rested and don't do anything strenuous, BUT keep your arm moving gently as much as possible. Even if you are sitting, raise your arm and do slow turns in a circle. Take tylenol and/or ibuprofin.
Start the special exercises when the doctor says to.

I would visit my sports therapist.