A pickup truck bed liner installation generally involves cleaning the bed, placing the truck bed liner onto the truck, and fastening the liner in place. There are two types of truck bed liners: drop-in truck bed liners and spray-on truck bed liners.
To install a drop-in truck bed liner, first use a broom to clean dirt and debris off the truck bed, wash the bed with a cleaning solvent and hose, and allow the bed to dry. Lay the liner over the bed. If you are installing a multi-piece liner, position one piece at a time, starting from the front and progressing to the rear of the truck. Use fasteners and, if necessary, bolts to install the liner in place.
For a spray-on truck bed liner, clean and wash the bed, sand the bed with a 36-grit sandpaper, and clean off dust. Use a car-safe tape to cover places you don't want to spray, and apply primer to the bed. Purchase a spray of your choice. Tune the pressure of the spray gun according to the manufacturer's recommendations, and test the spray on a piece of cardboard. Move 18 feet from the rear of the truck, and use direct long strokes to spray the bed, changing directions often.