There are many methods of treating mites, and many products with which to treat them. These treatments can be liquid, powder, spray or solid, such as pest strips. There are mite treatment products labelled and sold by some of the larger vendors of herp products. I've tried many methods over the years, starting with Dri Die which I used to get in gallon cans from George Funk of Philadelphia. Dri Die was nothing but a slica powder which dehydrated the mites and ticks and often the snakes. Now I have a simple method using readily obtainable items.
As a preventative many herpers use pest strips. I hang them in the herp rooms and change them out every month or so. The reason for this is that mite eggs can sit for a long time before hatching so, if you have ever had mites, there is a possibility of a return of them. Some also cut off small pieces of the pest strips and put them on top of or in cages. Make sure that it is a small piece and that the cage has some ventilation. Overexposure to pest strips in a confined area can cause some neurological problems, possibly death.
I won't cover the other methods of treating mites, such as coating the animals with oil. I'll cover what works for me. It may or may not be the best method, but it works for me so I'll stick with it.
My basic materials are water, pest strips, sevin dust (used on plants) and Sure Shot spider killer., all available at Walmart and other fine stores.
First I set up a tub with enough water to cover the snake and let it soak for a few hours, sometimes overnight, to hydrate it and to kill off many of the mites. While it is soaking I totally clean the cage and any permanent cage accessories such as water bowls or rocks. when the cage is clean and dry I then blow in some sevin dust to lightly coat the cage as a prophylactic measure. After putting in new substrate I spray the surface of the substrate with the spider killer.
I then let the snake dry completely, then put it into a clean rubbermade box and put on the lid to let the snake settle down. once it has settled down a bit I put some sevin dust on the tips of my fingers, lift the end of the lid and blow in the sevin dust, coating the snake and the bottom of the box. the snake will get it under its belly scales while crawling around.
After a few hours I take out the snake, rinse it off and let it soak again to hydrate it and to wash off any dead mites or eggs.
That should do it. The treatment can be done again should the mites recur.