To eliminate odors from a leather couch, start by identifying the source. If it’s a recent spill, use a clean cloth to absorb the liquid. For lingering smells, mix equal parts white vinegar and water in a spray bottle and apply sparingly to the affected area. Allow it to air dry. Baking soda can also neutralize odors; sprinkle it on the couch, leave it overnight, and vacuum thoroughly. For stubborn odors, contact a professional leather cleaner.