You know how you get ready to go on a weight-loss diet plan.
Maybe you buy a diet book. Maybe you copy the specific diet food pages and post them on your refrigerator. Maybe you buy a food scale and find a handy place for it in the kitchen. Then you might go to the store and buy all the diet food that your plan calls for.
Maybe you tell your friends, significant others, kids, parents, etc. that you are getting ready to start dieting. Maybe you pick the day you will start. Maybe you get a blank book or a notebook to keep a food diary. Maybe you weigh yourself and write down your starting weight.
All good. Now, if you can prepare for the non-food part of the diet as well, as carefully, then you're in business.
Maybe you can recall the last diet plan you went on that failed you. Make a list of at least five things that went wrong for you. For each thing, come up with your best idea about why it went wrong. Take those reasons and see if you can plan for them this time, before they actually happen. Maybe you can divide your diary into two parts - food diary and thought diary.