How many diapers?

Ever since I first found out I was pregnant my mom gave me the great idea to simply buy one box of diapers from Costco every time I go to help break up the cost. But now I have several boxes of diapers in varying sizes and I’m wondering exactly how many boxes I should buy? Does anyone have recommendations? Like I only bought a single box of newborn just incase she’s on the smaller side, but how many size 2, size 3, etc etc diapers should I buy so I don’t accidentally end up with more diapers than I know what to do with and waste money?