Channeling my college dance days here... Exhale drop knees to the right and swing the left leg and arm across the body inhale pass through center. Exhale drop to the left and so on. Go with gravity. Let go of effort and control of the body and give in to momentum (hidden life lesson!). Think of it as a pendulum swing with the greatest velocity reached at the bottom of the swing. It is a beautiful way to hydrate the hip and shoulder joints and turn off the thinking mind. Typically you would keep the swinging leg's big toe connected to the earth but it doesn't quite work with a non-slippery surface or yoga mat so I broke the rules and did it free floating and it felt good. I could do these for hours and hours.