Vacuum your wallpaper to remove dust and debris with the soft upholstery brush attachment on your vacuum cleaner.
Remove the wallpaper cleaning putty from its packaging. Choose an area on your wall that isn't visible, like behind a piece of furniture. Rub a small amount of the putty in a circular motion to remove dirt and debris from the paper. Vacuum the bits of loose putty that stick to the paper or fall to the ground.
Check your test patch to make sure the wallpaper cleaning putty didn't discolor or damage your paper. If your sample is free from staining or damage, repeat the process on the rest of your wallpaper.
Fill a bucket half-full with warm water. Add a teaspoon of dish detergent or other mild soap, like castile soap, and mix gently.
Dip a sponge into the soapy water and wipe down a small area that isn't visible, like behind a piece of furniture, and then check for staining or discoloration.
Dust your wallpaper with the upholstery brush attachment on your vacuum cleaner to prevent wiping dust into your wallpaper's texture and detailing.
Wipe down your wallpaper with long, smooth strokes in the direction of the seams. This is usually a vertical motion.
Let your wallpaper air dry or dry it with a soft, absorbent cloth. Avoid paper towels or other drying cloths that could leave lint on your wallpaper.