Well the amount of white fabric you'll need will be dictated by your pattern then, and I would add on an additional half yard or so (I like to have lots more than I need) for the gloves if you're making them as well.
For the bows, I think usually a yard is more than enough unless you're doing the Super, and the collar is about half a yard if I recall. The online pattern has dimensions, you'll want to check that. Are you planning on doing a circle skirt or a pleated skirt by hand or by a pattern?
Girls With Comics
Guess what, Japanime costume players....
YOU'RE NOT THE ENTIRETY OF THE COSPLAY WORLD.
Stop being so closeminded. Just because someone cosplays doesn't mean they're an otaku or a weeaboo.
Super Sailor Moon, Sailor Moon