The first step to removal is to know what your walls are made of. In most cases, walls are either drywall (gypsum sandwiched between layers of paper) or plaster smoothed over lath (either strips of wood or metal mesh). You can usually tell what you have by the feel (plaster is harder, colder, and smoother than drywall) or by tapping on it (drywall sounds hollow, and plaster doesn’t).
When in doubt, remove an outlet cover to see the exposed edges. Drywall is more vulnerable to water damage; you must avoid over wetting it. And use care when you’re scraping because drywall gouges more easily than plaster.
First, KNOW that this is going to be a messy job. There is no way around that. Bits and pieces of wet paper, covered in adhesive, will end up stuck to everything that’s not covered. Fortunately, it cleans up easily with some soap and water.
Wallpaper removal is a task no one enjoys. It’s messy, sticky and time consuming.
Some people try to avoid this tedious task by painting or re-papering over wallpaper, but this is never recommended and will become a headache for whoever attempts this task in the future.