Watch this video from This Old House to learn how to strip wallpaper.
1 Roll scoring tool over the entire wallpapered area.
2 Mix liquid wallpaper stripper with hot water in a garden sprayer.
3 Use garden sprayer to apply wallpaper stripper to wall.
4 Scrape softened wallpaper from wall with putty knife or paint scraper.
5 Use electric steamer to remove stubborn wallpaper.
6 After initial scraping and steaming, spray wall again with stripper.
7 Scrape away last bits of wallpaper with putty knife or paint scraper.
8 Scrub wall clean using coarse scrubber pad and clean water.
9 Use scraper to remove softened glue residue from clean wall.
10 Let wall dry, then apply new wallpaper, or one primer coat followed by two paint topcoats.