Score the wallpaper with a wallpaper scoring tool. Hold the scoring tool against the wallpaper and apply moderate pressure to perforate the face of the wallpaper. Do this sporadically throughout the wallpapered surface. This will allow the steam to penetrate the glue and backing.
Fill your wallpaper steamer with water and allow it to heat up according to the manufacturer's instructions. Operating instructions will vary among models so it is important to read the instruction manual carefully.
Hold the steamer plate onto the wallpaper, starting at the top of the wall and working your way down. Leave it on a section for about 10 to 15 seconds, then remove it.
Scrape the softened wallpaper from the wall with a putty knife. Take care when scraping not to gouge or damage the drywall.
Put the steamer back onto each section for an additional five to ten seconds if any backing or glue remain of the surface. Scrape again until it is gone.
Repeat this process throughout the entire surface until all of the wallpaper, glue and backing is off.