i always use a food diary, but not the ones you get from group-
what i did with them was to tape two together (lining one front and one back view together so it resembled an A4 sheet and had all the 7 days on one side)
then I photo copy loads and when ive filled them in I slide them into a A4 display booklet , so I can see at a glance how Im doing. I also have a spreadsheet that I fill in midweek- I put mine and OH weight into and we compare- OH has been losing the same 2lb for a year .and putting it back on LOL
I also have a spreadsheet for my measurements, I take them every 5/6 weeks or so .
So for me a food diary is essential