Have you tried the app myfitnesspal. It allows you to scan the barcode or manually input what you are eating. Today marks my 4th day post op and I started using it on the 2nd day of my preop diet I like it because it is simple to monitor what you eat. Plus you can add the cups off water. In addition you can track your exercise.
I agree with the walking...I'm 2 days post op. But the more walking you do the better. For me the hardest part is getting up and down off the couch. But once I'm up I try to walk around as much as I can. Good luck!
I like to tale the single serve the tuna pouches and mix them with a single serve plain greek yogurt. Combined the protein count is around 18/19 grams! It's really good and easy to pack for lunch. Plus it is feeling! Good luck and congrats on. Your weight loss so far!