I have a really hard time with weekends and my main problem is eating out (or ordering in) with friends. I've made a new rule for myself that helps and that is to do that for only
one meal over the weekend.
I make sure to eat before I go to a friend's house that way if they're all ordering pizza I can say "no thanks I already ate." If they are going out for dinner or something I just meet up with them later.
When I do go (since I do allow myself one meal out for the weekend) I often order an appetizer for my meal to cut down on the portion size. I've tried "only eating half" of my entree but that never works for me, if it's there I can't seem to stop myself! Or sometimes I will get a broth based soup and a side salad as my meal. I've learned to avoid the large size salads that most restaurants offer for dinner because they tend to have TONS of calories and fat! The side salad is really the only safe one IMO because it doesn't have all the add-ons and the big size. California Pizza Kitchen's Thai Crunch Salad has 2115 calories! (Here's an interesting link to a Yahoo Health article on the best and worst salad choices from popular restaurants
LINK)