When my GTP was younger I kept the humidity at a constant 50% with spikes by misting once a day. Now that he's a bit older I only mist every other day. With this I've had perfect sheds, strong feed response and zero other problems.

However, I personally know people who just keep a constant relative humidity of about 65% with no problems.

The main problem that I think most people have with young GTPs is keeping it too hot. I've found 83-84 degrees F is good for a younger snake, and 86-88 degrees F for an older animal. I also do about an 8 degree drop in temps at night.

Just keep an eye on him for signs of dehydration, and adjust the temperature/humidity accordingly.