Removing stains from car carpet requires a combination of proper cleaning techniques and suitable cleaning products. For water-soluble stains like food spills or mud, start by blotting the area with a clean cloth to absorb excess liquid. Then, apply a mixture of mild detergent and water to the stain and gently scrub with a soft-bristled brush. For oil-based stains such as grease or oil spills, sprinkle baking soda or cornstarch on the affected area to absorb the oil, then vacuum it up before treating the stain with a commercial carpet cleaner or upholstery cleaner. Stubborn stains may require multiple treatments or the use of specialized stain removers formulated for automotive carpets. Always test any cleaning product on a small, inconspicuous area first to ensure compatibility with your car's carpet material. After removing the stain, allow the carpet to air dry thoroughly before returning to normal use. Regular vacuuming and prompt cleaning of spills can help prevent stains and keep your car's carpet looking clean and fresh.