I have not found a way yet.
We are programmed to go after food when it is available (during our evolution that was part of how we survived).
So, refusing to eat in a great tasting food rich environment is an unnatural act.
Trying to reason with the parts of your brain that want you to eat – especially when those parts know food is about to become artificially scarce - is difficult.
As I said, focusing on the positives helps.
Maybe there is another approach.
Something along the lines of recognizing that you cannot win against these two parts of your brain so the only way to not lose is to find a way to not fight.
I don’t know how I would do this arbitrarily but I have found that when my job is super interesting, it is much easier to fast - maybe just keeping busy is a good answer here.
Of course, the other way to not fight is to not plan to fast - if it puts you into a negative binge eating cycle that is now another health hassle you have to overcome - maybe it is not worth it.