This should go to the female technique side. I have tried this out with some of my girlfriends and wish to share it with the women folks who read this site.
The method goes this way: You will need a cricket ball/Hockey ball and if either are not avaliable a tennis ball. Coat them with lots of Vaseline lotion or KY Jelly. Put them on a stool or a tepoy and then sit on it, grind your pussy and clit on it vigorously. Take full advantage of the seam on the cricket and hockey balls and also the hardness. Most of my girlfriends have a real HARD ORGASMs from deep within their belly. Let me know your experiences when you ladies try it.