One of the most important things to familiarize yourself with is serving sizes. Aside from some produce, the serving size and nutritional information is right there on the package!
Step 4 of 20/20 is Reading Labels, Measuring and Recipes with Nutritional Info.
What most people DON'T do, is measure. Do you really know how much 3/4 c. of Cheerios is? How about 1 c. of skim milk? You think you're consuming 200 calories, but are you?
One thing you should always do, and invest in, is measuring tools. It's funny cause I'll our some ceral into a bowl and be like, hm that looks like a cup and when I go to measure it, it's always more or less. This is something I'm definitely going to be more aware of.
Now about weighted measurements - it's not a bad idea to have a food scale. Did you know a serving of chicken is 4 oz.? You know how when you get the 6 oz. steak, it looks so small?
I saw these plates one time on someone's blog, that I really wish I could find again. They were plates that have the portion sizes already marked on the plate. If I find them, I'll post it!
Ash highly recommends picking up a nutritional info book with common ingredients serving sizes, calories and fat.
*Some of post adapted from Ashlee's Blog*