Temptation

I'm having these cravings and temptations during my pre-op liquid diet. I was instructed to be full liquid diet for 10 days before my surgery & I'm only on day one and "cheated" with a small bag of original lays. Any advice on how to substain from cheating?

I am doing 4.5 wks of optifast pre op. I did a week of not cheating but I also did not have the 7 supplements I should have. This weekend we had a birthday party planned and I ate dinner with everyone else. I am hoping to get back on track on Monday and I am hoping I can at least get through one day at a time. Any temps would be helpful.