This will need you to be phisically fit.
Get an erection, now sit down on your haunches with feet flat on ground and your buttocks touching the back of your calf muscles.
Raise your buttocks a little and bring in your hands pinning them between back of your Thighs and calf muscles. You will now have both hands to grip your penis. Hands should be well lubed. Grip your erect penis with one or both hands and start humping by raising and bringing your buttocks down in a rhythm. Since your hands a clasped shut between your legs this will give and incredible feeling of a real pussy.
You can control you speed and intesity...have a mind-blowing orgasm!!