Next time you notice he's going into shed use a humidity box. It's literally a plastic container big enough for your snake to fit in with a hole cut into the lid, and has damp moss inside. I line the bottom of mine with a paper towel to help with clean up and to retain water better. Some people will leave them in all the time (to give your BP options) but I've had my BP successfully shed for the 3 years I've had him by doing this