As with any paint or wallpapering project, be sure your walls are properly prepared. The walls should be clean, free of any dirt or grease and have a smooth finish.  ・Dust and then wash down the walls and moldings. ・If the walls have a rough or pebbly surface, a wall paper liner is usually recommended. ・Remove all protruding objects such as switch plates and hooks. It is usually best to remove any existing wallpaper previously covering the area and remove any residue left from the removal.  ・Fill any cracks, holes or damages with the proper wall filler, and then sand those areas smooth.