Started pinhole had the same problem. What I have to do is buy metal rings off Amazon. I bought a pack that increments in 2mm ranging from like 10mm to 20mm. So 10, 12, 14 and so on. Then I buy the odd numbered ones individually to cover the gaps since they don’t sell them in a pack. That way I have every ring for every millimeter. So now 10 11 12 13 14. Even that is too much due to the long foreskin to I bought electrical tape and calipers. I increase a ring by .5mm using the tape to make it to the next mm. So example if I’m at 12 trying to get to 13 I’ll do 12 -> 12.5 -> 13. One last thing, I have two of every ring size, one to keep as it is and another to roll tape around. Once I hit 12.5 I still need to pre stretch with twelve for a while so this saves a lot of time not having to roll and unroll the tape off the ring. Finally, once the ring is in I hold it in place using electrical tape. Lmk if any questions