How to Take Off Wallpaper from Plaster with a Wallpaper Steamer
Hold the hotplate against the wall until the wallpaper softens.
Starting at the top of the wall, hold the hotplate against the wall in one area until the wallpaper softens. The moisture drips down so it should help moisten the rest of the wall.
Both steam and the water it produces can drip off the hotplate and burn you. To prevent hot water from dripping down your arm, stand on a stepstool when you’re working above chest height. Wear rubber gloves and a long-sleeved shirt, too.