As far as cleaning goes, I usually only wash it about once every four to six months, if even that, really. I fill a tub part way with warm water, put in a bit of detergent, and swish the hakama around for a while, then I rinse it. I hang it up to dry afterwards for about a day then iron it to get the pleats back in nicely.
Taking care of a hakama is pretty simple. Jun makes it way too hard. Find a washer, throw some detergent in, follow it with the hakama and whatever else needs washing. Take your best guess as to a good temperature. I've tried many variations, all seem to work pretty well. When it's done, find a dryer and throw the hakama in along with whatever else needs drying.
Be sure to press the start button. It helps to do that during the washing part as well.
There's a bonus to my technique. If you wash your new hakama with some really dirty white clothes. You will get less dirty black or blue clothes. Yes!
Bet you guys think I'm kidding.