I organized my newborn and 0-3 month clothes by size and type in my dresser then in the closet I got a plastic cube storage from Amazon you can build it different ways so I liked that idea. I got cheap cube bins to go with that and just separated by size for all the larger sizes. I’ll rotate the next size into the dresser when he doesn’t fit in newborn clothes anymore.
I did get some small drawer organizers for socks and mittens and hats!