I stuffed up my rotator cuff a couple months after I began weight training. I got pretty bad impingement for a while, so I laid off any shoulder exercises for about 6 weeks or so.
I'd read about these exercises to strengthen the rotator cuff called internal and external rotations and then stumbled across a post from Fadi here where he linked a vid of Branch Warren doing them. In the examples I read online they were saying to do it lying on your side, but Branch Warren does them standing up...much more practical and less idiotic looking.
I've been doing 2 sets of both internal and external rotations at the start of every non-leg workout religiously for the last 7-8 months and its worked great. I won't stop doing them either, I think they're a great safeguard exercise at the start of a workout. Do a search to see how they're done.
I never did thank Fadi for that either. Thanks Fadi, you are a legend mate. Did you ever know that you're my hero? You're everything I wish I could be. Shiiiit, I'm getting sidetracked.
Good luck, have a Bonza time!