Marley - my closet isn't in very good shape either - and it's also because I have a closet that just isn't all that workable for me because it has three sliding doors (which are very narrow), so it's like playing musical doors to get in there. I can only have one 'section' open at a time, and it's a narrow section. To make matters even more maddening, the closet rod is suspended with several metal rod holders all across the actual bar - making it next to impossible to slide clothes across it. Aggghhh....
In any case, I really liked what Sylvie suggested..she was saying:
"One evening, try on all your jeans. The ones that you know you want to get rid of go in a box. The ones that are 10's get put away nicely immediately. The ones you aren't sure about go in a holding zone. Have a glass of wine and go to bed.
Day #2: Go through your tops.
Day #3: Go through socks, underwear and nightgowns.
Etc, etc.
The key is that anything in the giveaway box can't come out again. And it needs to get out of the house as fast as possible. Take it straight to the trunk of the car if that's what's necessary."
This advice appeals to me. Sorting further into colour and so on can happen later. I really like the "nothing but jeans for now" task, followed by "nothing but shirts and blouses" and so on.
Meanwhile, I wanted to add that one of the big frustrations in terms of closet cleaning for me is not having enough containers/boxes or whatever it is that I need - so I am making the suggestion that you buy a dozen of those "bankers" boxes - you can get them at Costco, Wal-Mart or any office supply place. Also buy some cheap clear page protectors over where the school supplies/binders are sold. These will be used for labeling the boxes.
The benefit of using these for "labels" is that you insert a piece of paper indicating contents inside the clear pouch and affix to one of the banker's boxes once it's full - but you haven't "ruined" the banker's box for future use. Simply remove the paper inside and put something else in there if you want re-label the box later for something else. Also, banker's boxes are sold flat, so they don't take up a ton of space - it's an "assemble as needed" situation, which to me is better than having a ton of those rubbermaid type totes hanging around.
Useful items: banker's boxes, clear shipping tape, 8x11 plain paper, clear page protectors.
The boxes stack up nicely, and you can't over-pack them to the point where they are too heavy to move around.
Good luck - you can do this!