This isn't so much a technqiue, but a question of technique.
When I masturbate I mostly stroke the tip of erection (the glans)with my fingers and thumbs. Sometimes I use a fist, but still stroking the tip. I've seen a few of my mates doing it over the years, and its the same - they stroke the tip too.
Looking around at some of the stuff that's on line a lot of blokes stroke the shaft and never even touch the tip. Why is that? I've tried it a few times, but it takes me longer to cum, and the last few moments when I'm on the brink are agony. I can't bear the waiting and I just can't cope with the agony of those last few seconds.
I like to stroke my shaft gently with my free hand, by running my finger tips up and down, or wrapping my fist around it, but I can't bear to masturbate slowly, or by any techniques that involve a delay. I'm over 25, but I still have to wank it off as quickly as I can.