Make sure he's secure in his cage with plenty of hides. A bitey ball python is a scared ball python.
A couple things I've tried in the past: Wadding up pieces of newspaper and putting them in his cage. This provides extra security/hiding places. It doesn't look nice and can be a pain to clean up, but this one has rarely failed to make a snake feel better about his surroundings.
Also, get a dirty tshirt of yours, something you've sweat in and didn't wash, and has a nice scent to it. Put that in his cage with him for awhile. It's gets him used to your smell. I've tried this technique with both boas and balls with mixed successes, but it's always worth a shot when you have a scared noodle.
Good luck!