Hellobee Boards

This might help! I had similar questions...
http://boards.hellobee.com/topic/how-is-your-los-dressercloset-organized

Also, to add to this--I found that I organized things one way but then completely changed it around when LO was born and I figured out how I actually needed things to be laid out. Right now, we have his current size and the next size up in his dresser (his summer stuff is all 6-9/12 months, so I keep it out as the weather is getting warmer, and his 3-6 month s tuff is pretty tight but we're still having some colder days and he doesn't have any long sleeved bigger clothes). I have it organized by short sleeves, long sleeves, leggings/footie pants, and pants (jeans, cargo pants, etc). We use boxes within the drawers to separate things. In the closet, I hung all his sleepers, and button down shirts, and I have a hanging closet organizer thingie with fabric shelves where I keep the next sizes up (12-18 months, etc).

All of her current sizes are in our dresser inside Ikea dresser dividers in our room (since her crib is outside our door). All other sizes are in her dresser in her room according to size. We bought her a huge dresser with a lot of drawers since that room has limited closet space. Her current size dresses are hung up in our closet.

When we move her into her own room, I'm also moving most of her clothes in there.

We have an Elfa system in her closet. Almost everything is hung by size and style. I also have a few drawers and baskets/bins in there for non-hanging items.

In her dresser/changing table drawers, I keep all her diapering and sleeping essentials. I keep one drawer with current sleepers and basics in rotation. That's the easiest to grab and go. Nice pieces are still hung. I think girls have more hanging clothes though?
As for size, I tried to eyeball them and keep them grouped by actual size and not always what the label says. I.e. All her Ralph Lauren stuff looks so small and always in a size group smaller.
I also use a lot of mesh laundry bags for baby laundry. I wash everything that has Velcro in a laundry bag because I don't want them snagging anything (esp A&A stuff). And I always flow all snaps.