First, choose the right hand tools. There are tools that create tiny holes or score your wallpaper making it easier to get moisture behind the material to soak it away from the wall. This has become a necessity particularly with stubborn old papers and the vinyl papers that were created to resist water. Putty scrapers and knives or plastic scrapers usually work the best for chipping away at wallpaper.
Use some liquid help. Mix some white vinegar and a little dish washing soap in HOT water to wash over the surface after perforating. You can also try fabric softener in your hot water instead of the vinegar and soap. You can sponge on the liquid, use a rag or spray it on with a plastic spray bottle. The latter is usually the easiest.
Do one area at a time in succession. Perforate the paper with the circular tool. Then soak the paper with the hot water solution. Wait for about a half hour (during which you can start the next section), then peel off the paper. Scrape or wash off any remaining glue using a little tri sodium phosphate (TSP )mixed in water.
Or try getting some commercial help. Some people really swear by wallpaper strippers like DIF wallpaper stripper. You can also rent a wallpaper steamer from your local hardware store or home center.
Hopefully, these suggestions will help make the job of removing stubborn wallpaper easier.