I like solid's idea lol. I think damp moss can help them shed if he's having trouble but i wouldn't worry some snakes can go longer than others without a shed. On the info my snake came with it says she shed a week after hatching then the next time was 5months & 5days after that, so if the info is right she should be due another shed in another 2months.
1.0 Bearded Dragon - Loki 0.1 Corn Snake - Smoo 1.1 Mexican Black King Snakes - Nameless