A good place to start is to keep a food diary so you can see what you're putting in your mouth everyday. Look for patterns and become a nutrition detective so that you can start replacing just any old food with nutrient dense options that are delicious. (which is plentiful if you take the time to look!)
A lot the empty calories we consume like bread, crackers, chips, candy, and sodas can be replaced with things like fresh food and veggies that are easy to grab and eat like a snack. The nutritional fiber in these foods will not only make you full but it will satiate your palette so you won't be scrounging for the "I'm still hungry" candy bar or ice cream pint.
Taking on the "Big Salad Challenge" (creating a salad with at least 5 different vegetables - the more the better - OTHER THAN lettuce) and eating that at the start of your main meals will help you to fill your stomach with much needed nutrients. Think of this, 1lb of meat fills only a small portion of your stomach while a the same amount of spinach not only fills you stomach but it gives you the same amount of protein!
We crave what we need and it's really not MORE FOOD but more quality food!