hope your doing well!!
I think the #1 is don't overeat just because it's provided and #2 is don't over indulge just because it's on offer. I.e. if you wouldn't eat it at home, don't eat it out.
if they offer dessert, don't think you HAVE to have it!
Also, if you can run to a supermarket, get your own snacks that you can eat that are better for you to have when they offer snacks :)