The easiest way I've found is to remove them from their home temporarily, toss/bleach (carefully) anything from there (toss the substrate).
Clean that tank out. Vinegar, bleach, or a ton of soapy, soapy water (soap and water takes a long time to fully work though).
Bathing your snake in soapy water will help dislodge the mites, and then drown them, but again this takes awhile.
There are also some "products" (Mite Away Sprays) that you could use (might need to scope online for the latest scoop on the products though) that can possibly help eliminate them quickly and safely.
I've used the sprays myself on my ball python and he was mite free in 2 days. You'll still have to strip his tank clean though.