Start by laying on your stomach. bring your hands behind your back like you're in handcuffs. Lift your chest as high as you can (like a superman) and begin to straighten your arms out, creating a big circle with your arms until they touch above your head. Keep trying to lift your arms away from the floor to strangthen all the little muscles in your back that promote good posture (and get forgotten about in day to day life) reverse the circle back to the starting position and repeat!