How do I change the utilities out of my name?

I am moving out of my apartment for the summer and want the utility bills out of my name. My roomate will still be here over the summer but I dont know her schedule for the remainder of the week. The company said that I contact the management to change names, Do I just go to them and say I want it out of my name or do I need my roommate there to change names?How do I change the utilities out of my name?
You need to call each of the utility companies and tell them that you want to terminate or cancel service. Your room mate then needs to call and set up service. They know that someone else will take over service so usually they leave on the service for a day or so until the new person calls to establish service.