Welcome to the board. :wavey I usually hate being 'the guy' that says this, but someone will eventually. There are TONS of posts on this board with some really great info. If you have a question that you think has probably been asked/answered before the best thing to do (for the quickest responce) is to try searching for it using the link at the top of the page. Usually searching for a question on the Detailing, and Autopia University forums will provide answers to all your basic questions.
Most people wash their MFs using laundry detergent. I tend to just throw mine in the machine with a little bit of dawn. You shouldn't use any kind of fabric softner or anything as it will leave traces of it behind which will get into the towells and then on the car. It's best to just use a little soap and warm water. The drying is just as easy. If you are going to use the dryer, don't put them in there long, or at high heat. It's best to let them air dry as the higher temperatures from the drier will start to kind of melt part of the fibers that make up MFs. I have some MFs that i found out the hard way on. They are definatly not as soft as my new ones from Pakshak.