It was a little confusing the first time I tried, because I was expecting it to pop or slide in differently that the way it does. From the top, if you push your testi up toward your pubic mound, it should sit kind-of inside the pubic mound, before slipping out very quickly. The idea is to get them both into that position (so that you can feel them under the pubic mound) and then keep them there with a gaff/tight underwear/tape etc. That's the easiest way I can explain it, once you find it, it's very easy and requires no force at all. And nope, doesn't hurt at all, it is a little strange feeling though. Like if somebody hit you in the pubic mound, you could be in very serious pain...