Take it off, Take it all off
Off the rod, off the rack, off the shelf. What you see is what you get and the only way to know what you've got is to see each and every piece.
Empty your closet and dresser of everything and neatly lay it all out on the bed or floor. Take this opportunity to vacuum, dust, re-paint, re-line and basically spruce 'em all up.
Separate the wheat from the chaff by dividing your garments into four piles:
wearable
sentimental/ costume
give away
throw away/ rags
Now work those piles in reverse order. Throw away's go in the trash. Just do it! Rags go in the rag box on top of the washer or under the sink.
Giveaway's go into a shopping or big trash bag and into the car for delivery to Goodwill, a neighborhood battered women's center or a homeless facility.
Sentimental and costume pieces should be hung in breathable garment bags or packed into empty suitcases and stored in an out of the way closet, attic or basement. Be careful of damp and musty spaces and use acid free containers for really delicate, valuable or ancient clothes.
Finally we're getting to the heart of the matter. Go through all your wearables and check for cleanliness and condition. Mend holes, re-attach buttons, clean stains or drive these necessities down to the dry cleaner to take care of. Now, let the good times roll !
A room full of studs
Throughout history the excess garments of fancy folks were kept in boxes or trunks until the sixteenth century when Good Queen Bess ran out of room to store her frocks. She commissioned the construction of a room studded with wooden pegs. One for each of her three thousand gowns. Along with her eighty wigs, twenty seven fans and God only knows what else, she finally had a place for everything and everything was in it's place - the closet.