I stuff a clear 17-inch tuftex balloon under my shirt with the camera below me knees looking up, and inflate it in inside of my shirt. I finish inflating in my shirt, then tie it. I then lay on it, bounce in it and hump it from several angles. I then take a bite out of it, which makes a small hole that air leaks out of, so the balloon slowly deflates underneath me until there is no more air in it.