Congratulations on your new snake!
You can bump the humidity up to around 70% while he's shed. A light misting or placing a wet paper towel or wash cloth in his cage should be enough to bump the humidity, but you might have to mist daily if you use a lamp to heat his cage.
Other than that, just leave him alone and let him do his thing. Oh, and to answer the question on the thread title... the shedding frequency depends on a number of factors including growth rate, quantity/size of feedings, etc. However, if your snake is eating an appropriate sized meal weekly you can expect a shed every 1-2 months.
Good luck!