hi TOF, (and Reb Shlomo, too)
Short on time, but not on advice:
1, If your problem is at night in bed, concentrate VERY much on Keriyas Shema Al Hamitah, especially the pasuk Rigzu v'al Techata'u... right near the end. That was written SPECIFICALLY with this aveira in mind. See Berachos Daf 4b or 5b (I think) where the gemorah discusses this pasuk and kavanos each word stands for. Follow the advice of chazal about sleeping on one's side, and which side to sleep on (fall asleep on your left side, awaken on your right). Wear PJs that cover your legs and your arms - even kiruv basar with your own body or sheets can be triggering. AND take a natural sleep aid to fall asleep faster, so you're not lying in bed awake. And in the morning, get out of bed asap and don't linger there daydreaming.
2. During the day, make 2 gedarim:
A) A physical Geder that your hands will NOT NO MATTER WHAT travel ANYWHERE near the bris. Realize that even if you want to give yourself just a little pleasure, you will not be able to control or stop it going further. Don't kid yourself, even if you can pull away now, it will awaken a stronger desire in you and then next time you'll make all sorts of excuses - "I need it, it's healthier to have release than to hold it back, I can't help it so Hashem must forgive me, i'll give in now and try later" blah blah blah, it's all a ploy of the YH.
A MENTAL Geder - A Rebbi once told me that when faced with an overwhelming struggle with a YH, break it up into bite-size pieces you can digest easily. If i start to think about women or images or fantasize, etc., I will stop myself and say - "I'm sorry mr. YH, but NOT now. I am not making any commitments about later, just NOT NOW." Say to yourself i will stay clean in mind and body until Lunch. No commitment for the rest of the day. When lunchtime comes, you can say OK, I can stay clean until dinner. That's no so hard. No commitment afterward. At dinner time, Oh, I can make it until bed. I'll worry about tomorrow later. And if every 4 hours is tough, then take it hour by hour.
You CAN do this.
Here's a good eitza to practice breaking your desires for fulfilling pleasure. I think it's the Raavid's Taanis - see Rabbeinu Yona's Yesod Hateshuva (Foundation of Repentance) found in Rosh Hashana Machzorim. At the end of each meal, leave over a littler bit, the last bite or two, from each course. It's NOT baal Tashchis, cuz you're doing it for a purpose. Say to yourself or out loud "I am doing this to show i do not have to fulfill my desire completely, in Honor of my Creator." Do this at every meal for at least a month. It is an amazing method to break the hold that teivos have on us, and it will make it easier for you to say no to the Big YH you battling.
3) lastly, get involved BEING OF SERVICE TO OTHERS. Build your self-esteem by benefitting other Jews through time and effort in a chesed organization. The more positive and better you feel about yourself, the more you insulate yourself against the negative depressive feelings that bring us to act out to make ourselves feel better.
Good Luck, and KOT!!