I don't know about you, but even when I would go through my closet before I was pregnant, I never want to get rid of any clothes. I guess I'm emotionally attached to them...even though I don't wear most of them. But, my husband is a great help in that area, he isn't sentimental at all. :) So, here's some tips I've learned on how to weed out your closet.
1. Unless you have a HUGE walk-in closet, only hang up CURRENT season clothes. I'm a huge believer in putting away winter clothes when winter is over, and pulling out summer clothes! Yes, there will be some pieces that are year round, but you should be able to put away a good amount when the seasons change.
2. Color coordinate your closet. No explanation needed other than it's so much easier to "see" what you have to wear when you know exactly where it is hung up at.
3. Separate skirts/dresses/tops. I keep my dresses all on the left side, my skirts on my lower rack, and my tops on the upper rack, all separately color coordinated.
4. Weed through your clothes! Go through your closet every season and give away all the items you know are outdated, don't fit, or you just don't wear! It is so much easier to create new outfits when you actually wear ALL your clothes. Be honest with yourself in this area, if you haven't worn in for 3 months (not because it was too cold, but just because you didn't wear it) then TOSS IT! :)
5. Create new outfits. When you get a free day one day, go through your entire closet and try on a bunch of new options and create new mental outfits, that you can go back to and wear later on. You can also take a picture in the ones you really like so you don't forget about them!