frontline makes a frea and tick spray that i've used for years on my snakes. don't spray directly to the snake spray the frontline on your hands and then gently rub it on the snake avoiding the face of the snake. then you can take everything out of the cage and lightly spray the cage with the frontline and let it air out. If you have any wood in the cage spray it really good the mites can live in wood for several days. The frontline you have to buy at a vet and it's kinda expensive but it's worth it.
Warm water
Actualy ticks are generaly easier to get rid of then mites
Clean your terrarium and desinfest or boil the decos you can. Replace substrate and use a very hygenic one like paper towells for now. Next after your snake has soaked you need to take out each tick individualy. DONT POP THEM! You need a pair of sisors. Cach the tick as near as possible to its head as you can. Then twist it clockwise untill it realleses its grip. Then desinfect the wound with betadine. It is also important that you know that it is allmost certain that your snake was wild cauth, wich isnt the best way to start with a ball python, wild cauths are prone to anorexia and a number of other problems including parasites
