Some people like to rent steamers. I'm not fond of them, I don't feel that they work anybetter than wet processess, they just cost more money.
Most wallcoverings fall into one of four catagories. 1 Heavy vinyl, which just pulls off and you hope it doesn't take the wall withit. 2, Papers like grasscloths, strings and designer fasions. These come off quite easily by soaking them with water. 3, Peelable vinyls. This is the kind you hope you have. The vinyl face peals off and leaves the backing paper adhered to the wall which is easy to remove by soaking pulling it off or scraping with a small taping knife. 4, Strippable lightweight vinyl. These are almost as easy to remove as peelables. With these, I try to pull them off first. If that doesn't work, then I sand the surface with 80 grit sandpaper and soak with water with a small amount of TSP in it.
The first thing to do is to try to pull the paper off dry. This should help you determine what type of paper you have. Usually a wet process is required. I use a compression sprayer (Garden sprayer, the type you pump by hand) to wet the walls. You may need to soak them several times to get the adhesive to soften. Once the paper is off the wall, soak the adhesive with the sprayer and use a clamshell sponge to wash the adhesive off the wall. Change the wash water often and when finished, give the walls a final rinse with clear water.