I go back and forth. When I was younger I usually just manipulated the foreskin up and down, but later I found that I really enjoyed tugging my foreskin up over the head pretty hard before I started masturbating, so the skin was extra pliable. I don’t have a super long foreskin, so this stretch became the way I could try to incorporate my foreskin into masturbation a little more.
I found that when I pull my foreskin down tight to the base I enjoyed the direct pressure on the head, both dry stroking and with lube. It was a kind of thrill to simulate how circumcised men would jerk off.
I now alternate, about 50/50 jerking with the foreskin or pulled back. I like to use a tight cock ring with ball slot like the Oxballs where I can use it to help hold the skin back and really lube up and stroke it without having to hold the skin, it seems to feel more “natural” of a simulation for circumcised. I also sometimes use a ring of tape around the base of my cock and roll the shift skin down over the top of it then secure another ring of tape around to hold the skin down. This plus the cock ring works really well to feel like I’m cut really tight. I love the feel of the direct stimulation on the head, but also on the inner foreskin just below the head, as well as the tightly stretched frenulum.
My wife and I enjoy masturbating together and after I did it like this she enjoys giving me handjobs like that too. A little dirty talk goes a long way too when she say things like, “look at your tightly circumcised cock” or things like that are amazing.