First, tape a drop cloth or some plastic to the floor, as this DIY job will quickly become messy because of the use of water or other liquid chemicals.
Removing wallpaper from drywall with a steamer is a common method, but it can be uncomfortable to work with because of the heat, and you may have to rent the steamer.
Some people prefer to use an equal mixture of water and white vinegar in a spray bottle. Soak the area with this mixture, and it should separate from the drywall.
The most efficient means of removing the wallpaper is using a stripping solution. Dilute it with water in a spray bottle first, and use a putty knife to help pry it loose.