First, the treatment method for a damp wall surface: If the walls in your living room are wet and even show signs of mold, it's important to address the issue before proceeding with any decoration. One effective solution is to apply an anti-seepage liquid to the wall surface. This creates a clear, transparent waterproof layer that prevents moisture from entering, helping to keep the wall dry and ready for painting or other finishes. If the wall has already been affected by dampness, allow it to dry for one to two months first. Once it's dry, apply a cement-based water-repellent slurry to create a moisture barrier. Then, fill any holes or cracks with gypsum putty. After it dries, sand the surface smooth with sandpaper. Finally, apply two coats of primer using a paint roller or sprayer on a clean, dry wall surface to prepare it for painting or wallpapering. Second, common issues when applying wallpaper and how to solve them: 1. Smooth Wall: If the wall is too smooth, it may not absorb adhesive well, leading to poor adhesion. In this case, lightly sand the surface to improve grip before pasting the wallpaper. 2. Powdery Wall: A wall that feels powdery or flaky should be sanded down to remove loose particles. After leveling the surface, apply a coat of varnish or use high-quality wallpaper adhesive. Wait until it dries before applying the wallpaper. 3. Patching Putty: When filling small holes or cracks, mix more white glue into the putty to make it stronger and less likely to crack over time. 4. Flat Putty: For easier sanding, add a small amount of white glue to the putty. Alternatively, you can use a mixture of gypsum powder and white glue instead of traditional putty. This helps speed up the drying process and reduces overall construction time. Profile Spot Light,Zoom Spot Light,Film and TV Light,LED Spot Profile Light EV LIGHT Guangzhou Co., Ltd , https://www.evlightpro.com