Fill a spray bottle or a pump sprayer with hot water. Add 2 tbsp. of liquid dish detergent.
Turn off the electricity in the room. Cover the outlets and light switches with plastic.
Place a dropcloth on the floor to catch the wallpaper glue you scrape off the walls.
Wet the area where you need to remove the wallpaper paste. Allow the water to soak for three to four minutes.
Scrape the glue off the wall with a paint scraper or putty knife. Scrape off as much of the paste as possible. Continue to wet the area and scrape until you remove all the paste.
Rinse the wall with clean water. Dry the walls with an absorbent towel.