I recommend Flip cloth diapers. They're made by the same company as BumGenius, but I think the Flip ones are better. They are a one-size diaper. I have the organic cotton inserts and love them, they also have stay-dry microfiber inserts. I'm not a fan of microfiber. One nice thing about Flips is that you can take out the insert and put in a new one, reusing the cover, so you don't need nearly so many covers, just lots of inserts. With a newborn you may find the cover often gets poop on it though. That improves as the baby gets a bit older.
Some people find it easier to use newborn diapers on a newborn, one-size diapers fit better once the baby hits 10 or 12 pounds. Flips fit newborns better than a lot of one-size diapers, though. They're also less bulky than one-size pockets.
I would get maybe 24 inserts and 8 covers and see how that goes. It's at least enough to start with and you can always add more if you find it's not enough.
I wash diapers every three days. Many people wash more often, three days is the longest you should go. I have a lot more diapers than I actually need, so three days is perfect for me. You need to remember to wash them before they're ALL dirty, or you'll have nothing to put on the baby while they wash/dry. I store the dirty/wet diapers in a hanging wetbag, then on wash day I dump it into the washer, turn the bag inside out, and wash it with the diapers. I use The Laundry Tarts detergent, it's cloth diaper safe and natural and smell amazing! It's more affordable than a lot of comparable ones. I follow the package directions for washing. Start with a cold rinse to remove traces of poop, then a thorough hot wash with the detergent. An extra rinse at the end is a good idea, too.
Coconut oil is the best diaper rash cream for cloth diapers. It's healthy and natural, and even antibacterial! It washes out of cloth just fine. Most creams don't. You can find it in a health food store.
I think cloth diapers are a lot of fun, I hope you find that as well! Good luck!