As with all exercises at the newbie level, any heavy girth routine will cause damage if you aren’t conditioned for it. When your penis finally learns the difference between pe exercise and play time, then try this. Also you need to learn the difference between a normal erection and engorgement. Get about an 80% erection to work with, then clamp it with your hand as with a jelq, this is a dry jelq but with an added part. Move the clamped hand up you shaft like a dry jelq slowly, but squeeze in more blood right behind it to pressurize the base and move your hand slowly to mid shaft, stop and reverse it back to the base, the entire time squeezing (like a kegel) to expand the base area up to the mid part of your shaft. Then repeat. Its hard to do and I only ever got 5 to 10 reps before I lose my “erection”. If I’m not clear enough on the process, just ask.