Lay drop cloths over flooring, furniture and other objects to protect them from overspray.
Shake the can of Varathane spray polyurethane vigorously for three minutes before use. Shake the can at various intervals while using the product to keep it well-mixed
Hold the spray can 10 to 12 inches from the surface of the object you are finishing and spray in long sweeping motions to avoid drips and runs. If runs and drips appear, touch them up with a foam brush. Apply one light, even coat at a time for best results. At least three coats are recommended for a durable finish.
Allow each coat to dry thoroughly. Varathane spray polyurethane dries to the touch in two hours and dries hard in four hours. For a smooth coating, sand the finished surface with a 220-grit sanding pad between coats (called buffing). Remove the sanding dust with a tack cloth before spraying a fresh coat.
Hold the can upside down and push the button to clear the nozzle if the can is not emptied. When the nozzle is clear, only compressed gas will come out of the can. The can is then ready to store.