From what I remember the preop diet was low carb. I would buy the premade hamburger patties (from walmart) and bake them all at once in the oven. Put them in the frige and heat them up when I got hungry. Used mustard and mayo. Also, I ate a lot of eggs topped with salsa. Another great thing I enjoyed was bacon. Again I would cook a whole pound and eat it throughout the week. Cooking in bulk made things alot easier!! As long as there are NO carbs in what you are eating it should be fine to eat as much as you want. The importance of the diet is to shrink your liver!!! If they go in and you liver hasn't shrunk enough they won't beable to do the surgery.
The thing that made it the easiest was knowing that this was going to change me for the rest of my life. That helped me push through the preop diet. Just one small step to a new life!