To learn this trick the dog must have mastered the command down.
We kneel down near the pooch (around his head) and guide him with delicacy to lie down aside. We praise the dog and him give a delicacy. The next step is turning on its axis. Here, too, we guide dog with delicacy, but we do not stop in the lateral position, but urge dog to completely turn up. At the same time we pronounce the command "roll over".
We reward dog when he lands on the other side.
Over time, we should use more delicate hand movements so that ultimately doggy reacts only to finger circles.