Portions, portions, portions. Keep it simple. Instead of actually measuring, which is unrealistic and can turn into being obsessive, you can use smaller serving ware, plates, utensils, and storage containers.
Instead of eating off of entree plates, try salad or appetizer size plates.Purchase spatulas that are in 3-4 ounce protein serving portions.
Serving spoons that equal 1/2 cup for grains and double it for vegetables. Storage containers to pack your lunch that are in 1/2 cup, 1 cup, and 2 cup increments.
Keep it simple and purchase single serve individually packed snacks. Make being healthy easy for you!