Sized Pocket or All-in-One (AIO) diapers
Newborn sized modern cloth diapers are very convenient in the first few weeks. With AIOs, there's no extra work other than laundry and aside from washing the diaper, they function very much like a disposable diaper. Pockets are also convenient, but you will have the added step of stuffing the pocket after washing. These diapers are easy to use and can be such a blessing when your life is turned upside down by a newborn that needs to eat around the clock and is depriving you of precious sleep.
The downside to using modern cloth diapers in newborn sizes is that they can be expensive and your baby will most likely outgrow them within a few weeks. They will fit great from the beginning (and the diapers are so tiny and cute), but your little baby will grow so quickly that you won't get much wear out of them. On the flip side, some babies are born larger than others and you may find that you get much less use out of your newborn diapers.
Prefold or flat diapers with covers
Prefold diapers typically come in sizes. You can purchase a newborn size and they will fit your baby from birth. Flat diapers are usually one size, but can be folded down to the size your baby needs. You will only need a few diaper covers, since most of the time you'll be able to reuse the diaper cover between uses. This is the most economical option for a newborn size diaper. Once your baby grows too big for the prefolds, you can use them as burb cloths or as an insert inside pocket diapers. Flats can be used until your child is a toddler! You will only need to add a few new diaper covers into the mix in a size that fits your growing baby.
The downside to using flats and prefolds is they aren't as easy and convenient as modern cloth diapers. They aren't hard to use, but you will want to research folds to fasten the diaper onto your baby.
One Size Diapers
Many one-size diapers claim to fit from "birth to potty training". Depending on the diaper (and the size of the baby at birth) this may or may not be true. Typically, birth to potty training means somewhere around 8-35 pounds. Not all newborns are born at 8 pounds. Some 10 pound babies still don't fit well into the one-size diapers. It really depends on the shape of your newborn if the diaper will fit properly. You could take your chances with a stash of one-size diapers, but you may find that they aren't going to fit right away.
Did you cloth diaper from birth? What diapers did you use right away?