All surfaces must be smooth and sound, free of dust and peeling of inferior paint. Use of a pulp or acid-free liner is necessary. Writing on the wall to aid in the installation should be done with a light pencil. Never use a ballpoint pen or marker, as they will show through. Old Walls: Remove existing wallcoverings and sand. Wash and clean thoroughly to disinfect and eliminate mold and bacteria. Patch and sand as necessary to achieve a smooth surface. Prime with a universal wallcovering primer (T9000, Sheildz, 1-23). Do not use oil-based primers. New Walls: Smooth, eliminate dust, and ensure room temperature (55 degrees F or warmer) for at least 12 hours prior to installation. Properly prime walls: Latex paints must be cured with a product such as Gardz. New plaster must be properly cured (60-90 days) and feel cool to the touch.