Some people swear by prefolds for NB stage, however you want something that's going to dry quickly if you don't have lots of them. Maybe a few of each kind? Bamboo and cotton. The bamboo ones would probably make great boosters for other flats later on. I personally just used flanny flats until bubs was a bit bigger, then moved to terries. I still use the flannies sometimes, like if it's only an hour or so before DS's bath. They are pretty multi-purpose, especially if bubs is a bit of a chucker like mine was!

P.S. My nephew's name is Numa! Love it!