Wallpaper can be expensive, and it takes some work to get it up correctly. You'll want to keep it looking new without harming the design. Here is the best way to clean your wallpaper without damaging it.
Dust the Surface
Start by removing dust. Use a soft cloth and swipe over the surface to remove any cobwebs and grime.
Prepare Cleaning Solution
In a bucket, mix tepid water and a few squirts of dish liquid. Take a sponge and squeeze it a few times to get it saturated with the solution and then squeeze out the excess. You don't want to get your wallpaper very wet. Wipe down the wallpaper gently. This should be all that is necessary to get it clean.
Rinse and Air Dry
Change the water in the bucket to cool, clean water. Use the sponge again to rinse the soap from the wallpaper. Again, be careful not to saturate your wallpaper. After rinsing, allow it to air dry completely. If you notice any spots you missed, repeat this process on those areas.