Start in the cradle and make the cradle to palm roll. You now have the ball in your palm, extend this motion into the beginnings of a curl. Halfway through the bottom rotation of the "curl", your fingers are pointing straight to the back. This is the point to raise your hand/arm. So that the ball gets its upward motion and rolls over the outside of your wrist and the "cutting edge" (opposite of the thumb) of the hand to the back of your hand. When learning this move its easyest to first simply throw the ball up, rotate your hand and catch the ball in the cradle position. Then, just as in learning the cradle to front roll, start lowering this throw, until the sphere is actually rolling smoothly over your wrist. From the back of the hand the ball automaticly rolls into the cradle, and you're back into the starting position. To make a nice flowing move I used the palm to palm pass followed by the back to back transfer before doing the trick again.