Randa found a way to take some of the guesswork out of formula feeding:
There are times when you are out and about, or have your baby with a sitter that you just never know how much formula you're going to need to make. This also comes into play when you're pumping and never know how many ounces you're going to have to give the sitter, and how many ounces of formula they'll need to supplement with.
Instead of toting around the entire formula can, we use the powdered formula dispenser by Sassy that has the 4 sections, and we've marked the sections 1/2, 1, 1 1/2, and 2 and put the correct number of scoops in each section. That way you can make just as much formula as you need and can combine the amounts in each section if needed to come up with the right amount.