Grease, cooking oil and makeup on carpet

Oil does not dissolve in water, which is why a greasy spot on the carpet just spreads when you scrub it with a wet cloth. Cooking oil, butter, salad dressing, foundation and lipstick are all oil-based stains and they all respond to the same approach: absorb, then dissolve.

For a fresh spill, sprinkle cornstarch or baking soda on it and leave it for fifteen minutes to draw oil out of the fiber. Vacuum it up. Then apply a small amount of dish soap (a degreaser) directly to the spot, work it in gently with your fingers, and blot with a damp cloth. Rinse with plain water and blot dry.

Traffic lane grease

The gray path from the front door to the kitchen is partly ground-in grit and partly oil from shoes and skin. That combination bonds to fiber and no household product shifts it, which is why traffic lanes are pre-treated with an alkaline degreaser and agitated before hot water extraction. This is the single biggest visual difference professional cleaning makes.

Makeup

Foundation and lipstick on a bathroom rug or bedroom carpet are oil plus pigment. Treat the oil first with dish soap, then the pigment with a small amount of rubbing alcohol on a cloth. Mascara is often water-resistant polymer and needs the alcohol step first.