If you are looking to tone up, then exercise is the key (and, based on my number NOT my area to give you advice on). I really don't think at that level that cutting calories is going to do a whole lot of good.
But if you want to go that way, I suggest writing down everythign you eat..and I mean everything down to that piece of gum. After a week, look at it and see where the next week you can avoid pitfalls like soda and junk food.