keeping a pet snake is a bit harder than some people may think.
It would be a good idea to get a cage, make sure it's clean. Hook up the heat mat and thermostat. Lay in the substrate, place a couple hide boxes in place, fresh water and a secure lid, and then monitor the temperatures for about 2 or 3 days. You'll probably have to move things around a little bit, and maybe adjust the thermostat a time or two.
You want to make sure everything is "Right" before placing the snake in there. Otherwise he will be uncomfortable and it could even be harmful to his health.