I've taken down so much wallpaper I think I'm an expert... I've found a few ways to do this. Use the easiest method and work your way to the more difficult method:
Easiest
Pull up corners of wallpaper and if the wall was prepped properly, it just needs a good cleaning.
Moderate
Pull up corners of wallpaper which will peel off leaving the backing stuck to the wall. Use DIF concentrate wallpaper remover and warm water. Apply generously with a large nap paint roller - assuming you have a large section to do. If you only have a small section such as a border, use some sort of mister. Every few minutes see if it will scrape off with a large scraper (12" or bigger). it should lift off easily in large sheets without much scraping required. The key here is to allow the DIF to do it's work.
Difficult
If the corners of the wallpaper will not lift, try scoring it with a wallpaper scorer. It creates small perforations in the wallpaper to allow the DIF to soak through. This method could take many many passes with the solution. One room took over an hour and 6 passes with the solution to cleanly lift from the walls.
Most Difficult
Sometimes the wallpaper just will not lift without ripping the drywall. This can be because of some sort of super glue, or because it was applied directly to drywall before(I have seen it Sharidan). In these cases I've resorted to 3 different options. I've re-drywalled over the existing drywall (you can purchase 1/4" thick drywall), skim coated over the drywall with dryall mud, and I've had to gut all the drywall and put in new drywall.
Pick your poison. One of those methods will surely work for you. I highly recommend the DIF solution. You can use your own acidic solution, but I've found the DIF works the best. I apply it like I'm painting to make sure the walls get a good wet coat.
Either way - once the wallpaper is down - you need to prep the walls. Spend some time getting them smooth and getting all the glue and solution off the walls.