Sprinkle the cornstarch over the grease stain. Let it sit overnight. This will absorb most of the grease that is on the surface.
Vacuum up the cornstarch. Cover the entire stain with Murphy's oil soap. Scrub the stain in a circular motion with the scrub brush.
Wipe away the oil soap with a damp cloth. If the stain still remains, reapply the oil soap and scrub. Wipe clean with the damp cloth.
Mix together 1 tablespoon of Murphy's Oil Soap in one cup of water.
Blot the grease stain with the soap solution and clean cloth.
Mix 1 tablespoon of ammonia with 1/2 cup of water. Blot the stain using the solution.
Wipe the stained area with a clean damp cloth.