Lay a plastic drop cloth on the floor to collect dripping liquid and wallpaper as it falls.
Puncture the wallpaper with a perforating tool, using a ladder to reach the high spots. Run the tool over the wallpaper to make tiny holes in the paper that will allow your wallpaper-removal fluid to soak through.
Combine 1 gallon hot water with 2 cups white vinegar and 1 cup baking soda. Mix the ingredients well, making sure the baking soda is stirred in.
Sponge your wallpaper with the vinegar and baking soda solution. Soak the wallpaper to make sure your solution gets through to the adhesive. Allow the solution to work at loosening the adhesive for 10 minutes before you begin to remove the paper.
Lift the top edge of the wallpaper by gently scraping down and away with your scraper. Pull the wallpaper off the wall with your hands. If you're lucky, the wallpaper will come off in one or nearly one sheet. If an area is more stubborn, apply more wallpaper removal solution and allow it to soak in for a few minutes.
Wash your walls with a mixture of 1 cup ammonia and 1 gallon warm water to remove any baking soda or wallpaper adhesive residue. Dry with a clean towel. Before you apply new wallpaper or paint your walls, allow them air dry for 24 hours.