Kettlebell Windmill
The kettle bell windmill is an excellent exercise for promoting flexibility in the hips, spine and torso; in addition to developing strength in shoulder girdle, buttocks, and hamstrings. Here’s how to perform the windmill. Begin by bringing the kettle bell to the rack position shown in photo 1. Pivot your toes about 45 degrees to the left. Press the kettle bell overhead to the lockout position. Keep your eyes on the bell and push your hips out to side and begin to fold at the hips. The right leg is kept straight throughout the movement. Be sure to keep your elbow straight and armpit tight. Go down as far as you can, hold for brief second, squeeze your buttocks then return to the lockout position and repeat the sequence.
Picture 1 The lockout
The windmill 
Be sure not to twist, follow the same plane going up as you went down. This is not a fast movement; in fact keep your repetitions low between 3-6 repetitions per side. This movement is guaranteed to develop tremendous shoulder stability and increase flexibility in the hips, both valuable assets to your game.