Lay several lengths of rolled plastic on the floor to protect it from the water and vinegar mixture and the wet wallpaper that will be removed.
Remove as much of the top layer of wallpaper as possible using a 6-inch drywall knife as a scraper. When wallpaper is applied, a material called sizing is often applied first, and it is the sizing that may be the most difficult layer to remove.
Mix one part vinegar to two parts water in a spray bottle. If the area is very large, a pump sprayer may be used to make the job easier.
Spray an area of the wall from top to bottom and 6 feet in length. Soak the wall thoroughly with the water and vinegar mixture. Let the mixture soak in for 10-15 minutes.
Scrape the area with a 6-inch drywall knife. Hold the knife at approximately a 45-degree angle to the wall. Push the knife in even, smooth strokes across the wall.
Spray the wall again with the water and vinegar mixture if all the paper was not removed in the first attempt. Sometimes it may require several repetitions of wetting the wall and scraping to remove all the paper.
Wipe down the wall with a sponge and hot soapy water to clean it in preparation for painting or re-papering.