Mine says "wash seperately in warm water, tumble dry low or air dry no fabric softener or bleach"
I take "wash seperately" to mean "not with your laundry" which is kinda common sence since they are, technically speaking, rags saturated with chemicals.
I usually soak mine before I wash with some Woolite and sometimes a bit of Oxyclean. I then rinse them and then wash them on their own in the machine with Woolite, no fabric softner. Air dry and they are ready for use again. Handwashing won't get everything out in my opinion.
I use the pinnacle microfiber rejuvinator that i got with my CObra MF order. It works really great. I usually have around 10 MF to wash at once since i clean my car weekly and need to use a few MF. THat MR works well.
I wash in cold and tumble dry. After they dry its a little hard to get them unstuck since they are so staticky .