4. Not Using a Level
Unfortunately, sometimes walls and ceilings are just not level. Don’t make the mistake of lining up your wallpaper with the edge or corner of the room. A laser level or plumb bob tool will keep you in line and save you a lot of frustration.
5. Tearing the Wallpaper
When installing wallpaper, you’ll find yourself trimming edges often. If you’re not using a sharp razor blade for each cut, you may tear the wallpaper instead of creating a clean trim. Be sure to buy plenty of replacement blades and use a straightedge for each cut.
6. Not Wiping Away Excess Adhesive
Cleaning off adhesive is easiest when it’s still wet, so don’t wait until the end of the project to clean up. Using a damp sponge, easily remove the paste from your beautiful new wallpaper as well as your trim, ceiling, or baseboards.