Turn on your air compressor and set the pressure gauge to 80 to 90 pounds per square inch (psi).
Connect an air hose to the nozzle on the side of the compressor.
Insert three drops of nail gun oil into the air connector on the end of the nail gun to lubricate the gun. Place a rack of nails into the nail gun's magazine, then attach the hose to the air connector.
Put on safety goggles. Depress the tip of the nailer onto the wood to be nailed, and depress the trigger. If the nail doesn't sink until the head of the nail is flush, turn the rotary knob on the side of the nailer head just above the tip clockwise one full turn, and test the nailer again. Continue rotating the knob and testing until the nailer is sinking nails properly.
Increase the air pressure on the air compressor pressure gauge in increments of 5 psi if turning the knob on the nailer doesn't completely sink the nails. The combination of the adjustment on the nailer and additional air pressure will solve the problem.