Paper napkins are fine. The point is just that it's white, dry, clean, and disposable. There are various articles online about dealing with mites. Here are a couple:
https://www.lllreptile.com/articles/...h-snake-mites/
http://vpi.com/publications/the_life...of_snake_mites
Also, while you clean and sanitize everything in your snake's enclosure, do the same to everything around the enclosure as well that your snake or any furnishings might have touched. If you set your snake down on the bed or the floor while handling or whatever, clean those surfaces too. At the very least, treat anything your snake or his decor might have touched as a source for possible re-infection for awhile. Also, let the breeder know about the mites, as well as any pet store you bought supplies from. You don't know for sure where they came from, but either of those parties should want to know about it ASAP if they have a potential mite problem.
Ugh, good luck in dealing with this!