Hi, "Rookie",
It looks like you just joined the Board. Welcome! If you do a search on your topic you will find a wealth of information from those much more experienced than myself on this board. After doing the Main Trail a couple of times, I wanted something different so I did the New Army Pass loop solo last week and had a blast.
I spent one night at the Horseshoe Meadows Campground prior to starting. Spent my first night out at Long Lake, 2nd night at Guyot Creek, 3rd night the tarns just above Guitar Lake, woke up the next day and hit the summit and went home.
It sounds like you want to go quicker than I did. So if you go Cottonwood Pass you'd want to get to Rock Creek for the first night. Fill up on water at Chicken Spring Lake - there is a small water source after that, but you need to know where to look. If you did New Army Pass I would think you'd want to get at least to Rock Creek Lake for the first night. That 2nd day would be long, though. However, like I said, there is a lot of information on this Board, and you will have several options to planning your trip. Hope this helps!
Brian