Generally people say you shouldn't handle a snake for 2 weeks. I usually let mine sit a week before I bother them for pictures and whatnot.
The reason you want to give them time to settle in is because ball pythons stress easy. If they get stressed they stop eating, so it's best to keep them from getting to stressed. Ball pythons don't need to get used to their handlier, they are docile snakes so they aren't going to become aggressive just because you don't hold them.