Shut off the gas control valves on the front of the grill by moving the knobs to the upright "off" position.
Twist the connector located on the end of the regulator off of the nozzle of the old gas tank. Do this by turning the black knob on the end of the hose counter-clockwise.
Remove the empty tank by lifting it off the stand below the grill. Set it aside. Place the full gas tank on the stand below the grill.
Turn the valve knob on top of the new tank clockwise to verify the valve is shut off.
Connect the coupler on the end of the grill regulator to the nozzle on the new tank. Do this by turning the coupler clockwise around the external threads. Tighten by hand.
Open the valve on the top of the tank by turning it counter-clockwise. The grill is now ready to light and pre-heat in preparation for cooking.