Anyone know some good self-ballbusting methods?

Hello everyone, So I’ve had some fondness for ballbusting for at least a couple of years now and was wondering if anyone had any brutal self ballbusting methods? I don’t have anyone to kick me in the balls so I try to do it myself. I’ve used string to tie up my balls and I hit them with a boot but I want something that hurts more (like a real kick). Any advice is appreciated🙂