Chastity and orgasm denial discussion

I couldn’t track down an earlier thread about this (which might mean it hasn’t been discussed yet, or maybe my search abilities are slipping:p), so here goes: A local Domme who is aware of my interest in chastity told me when I returned home from an interstate trip last Saturday that if I was a good boy and stayed locked up (or avoided touching myself while not locked, since she knows my current cages aren’t comfortable enough for continuous wear) until the party this coming Saturday, she would give me a nice (== hard and painful:p) flogging! However, so far she has given me permission to edge as long as I don’t cum… but both times I had barely begun when I started leaking:( I’ve always preferred the build-up to the finality of cumming, but usually have trouble telling when it’s about to happen until right before it hits (and then I can’t do anything except giving myself what I understand to be a ruined orgasm by taking my hand away), but when I haven’t cummed for a while (either because I’ve locked up or lacked privacy for a few days) then I can’t take much before I start leaking:s Does anyone have any tips/suggestions on how I can prevent myself from cuming/leaking? All that I’ve found has been in terms of numbing creams and the like, which from my understanding would also stop me from enjoying the actual edging process as well:s