if it's torn you'll have to see a DR and surgery may be in order. Strained or VERY slight tear, I used light cables and very light dumbells, you can use the rubber bands too. Most of the exercises had the elbow down against your side, set cable at bewb level and pull across your chest and to your chest, both ways. Very light front raises and side raises. Depending on the severity, you may lift only a couple of pounds to a little higher but progress is slow.
I also had unintentional rehab that helped trememndously. My son was in t-ball and learning to catch a ball. You start off close and underhanding the ball. As they get better you move to a little further distance and having to overhand the ball, next thing you know it's 3 months later and you are starting to get 20-30 yards apart and throwing the ball pretty hard by then. That was when I noticed that my shoulder wasn't hurting, but I was'nt thinking about rehab, I was playing ball over those months and it just got better....