Pull out the measuring cup and the scale once or twice just...

Pull out the measuring cup and the scale once or twice just for practice. You don't have to do it all the time, but you see what it actually looks like. If you don't want to do that, use some of the visuals just to give you an eyeball, like 3 ounces (of meat) looks like a deck of cards. You don't have to be exact, but you want to have a clue.