Portion Size

Most foods are marked with portion size and most recipes are too. It's helpful if you just keep track of how much you're eating first so you can see what you are normally eating. People are amazed at how much more they are eating than they thought. We are newly using a restricted calorie diabetic diet and amazed at how much we get to eat and was still losing weight. Most servings are either 1/2 cup, 3/4 cup, or one cup.

Get a digital kitchen scale and weigh, weigh, weigh! I weigh just about everything, even fruits and veggies (hey, they have calories, too!). Most foods have two "serving sizes" on the back - by cup, or by weight. The weight measurement will be more accurate. I usually use grams and find a listing in MFP that gives calories by grams. It's much more reliable. For example, a serving size of regular and premium ice creams is 1/2 a cup, but the stuff that's more "whipped," 60g = 1/2 cup, while with the denser stuff, 100g = 1/2 cup. I find that confusing - plus I can pack a lot of ice cream into a half cup So I just weigh!

Input what you want to eat, portion wise.
You will probably change your mind, very quickly, after that.
Speaking from three weeks experience.