All my ferret does is bite everyone, how do i get him to stop and be nice?

First, biting. When a ferret is caged for long periods, they will start to bite. I rescued many a ferrets who people claimed are biters, only to find out they were caged to much. When he goes to bite, scruff him and say NO firmly, do not yell. DO NOT EVER FLICK the ferret on the nose, this can cause permanent injury!!!!! As far as litter, what are you using? DO NOT USE clay litter for cats. Pick his poo up and put some in the litter box. When you see him squat, pick him up and put in litter box, and keep doing it, praise him when he goes.