• When spraying the primer apply a wet coat with a standard spray paint gun over the entire area which is to receive the bedliner material. Make certain that you concentrate the primer spray on seams, tape lines, bolt holes and high abuse areas.
• Step up into the bed and begin by spraying the front of the bed first. Then the sides. Be sure to spray up under the side rails to insure adhesion.
• Spray the floor next starting at the front of the bed and working your way out of the bed. Once again insure that you  concentrate the primer spray on seams, tape lines, bolt holes and high abuse areas. 
• Appearance does not matter at this point. Don't worry about runs or drips.

NEXT It's now time to mix the bed liner material while the primer dries.