This is good, I need to add this to the FAQ's.
Since you just got this snake, you need to leave him/her alone for at least 3 days. No touching, no poking, no prodding.
It sounds like the snake has already shed but it did not come off in one piece. I'm going to paste one of my working FAQ question in here to answer this, as I'm too lazy to re-write it.
Q: I think my snake might be starting to shed, but I'm not sure. How do I tell?
A: First, your snake will begin to appear lackluster and dull. The colors will start to fade and on most snakes they will have a waxy looking tint to them. Their belly checkers (provided they're black) will look milky and their eyes will blue. If their eyes are blue, that is called 'blue phase'. After the blue phase, their eyes and skin will clear up and they will shed within 3-7 days, or thereabouts.
Q: Okay, my snake shed, but not all in one piece--what's wrong and how can I fix it?
A: This is one of the easiest problems to fix, so worry not. Bad sheds are caused by low humidity. So, you need to figure out what the humidity level is in your cage. You can either buy a dial like hygrometer from a pet store, or buy a combo humidity/temp guage from stores like Walmart. They are normally around $5 for the dial types, and $15 for the dual digital humidity/temp guages. Obviously digital is better, but both work. You are looking for humidity between 40-50%, give or take. Once you notice your snake start the shedding cycle, you can mist the cage once or twice a day to increase humidity or create a humid hide. Bigger water dishes also create more humidity. If you have a screen lid on a glass aquarium, you can place a towel of half the top to help keep some humidity in.
Q: My snake shed, but there is a piece of shed skin still stuck on the tail. Do I need to get this off, or can I just wait until after the next shed?
A: No, you need to get that off. Shed skin becomes tight and constricts where it is left after a shed. If the very tip of the tail does not shed properly and is not removed, it will constrict the flow of blood and kill the tip of the tail. You can either place your snake in a damp pillowcase for a few minutes, place your snake back into it's cage with substrate removed and replaced with paper towels or newspaper and a damp crumpled paper towel, or (and my suggestion) get a damp facecloth and let your snake 'crawl' through that until all of the skin comes off. This works very well for retained shed patches of skin that have not come off as well.