First soak your snake in a bowl of water with one or two drops of dish soap. While the snake is doing that clean all of the things in the cage with a bleach/water solution and then return them to the cage, spray the entire enclosure with Provent-A-Mite (except the water bowl) and put down paper towels in the enclosure as a temporary substrate, then put your snake back in its cage and regularly check to see if you notice anymore mites crawling around.

Hope that helps