Use a clean, lint-free cloth to wipe away dust from a car interior and vacuum up any crumbs if necessary. Use a suede brush or the rough side of a double-sided sponge to brush off suede upholstery.
Identify any upholstery stains and use an appropriate remedy to lift them from the leather. Try hairspray to remove ink stains, ammonia to remove blood stains, cornstarch to remove grease stains and vinegar to remove any unknown stains. Test stain removal remedies in an inconspicuous corner of the leather before applying to the stain to make sure they don't further damage the leather.
Mix two parts linseed oil to one part vinegar to create a home remedy to clean your leather car seats. Do a patch test before applying it to make sure it removes dirt without discoloring the leather. Work the solution into the leather and let it sit for several minutes; it may foam slightly. Wipe off the solution with a clean, damp cloth.