Flings are another great warm-up exercise that dynamically stretches the shoulders, chest, groin and hips. These are done very similar to jumping jacks.
The beginning of the fling has you starting looking like a "star" i.e. your hands are straight out to the side and legs are held wide. From this position, cross your right arm over your left and your right leg over your left. Go back to the "star" position and reverse the process. The pictures will help you more than this description!