1/2 cup isopropyl alcohol
1-1/2 cups water
1/2 cup vinegar
Mix ingredients. Store in a clean glass jar with a tight-fitting cover. Apply solution to leather upholstery with a soft cloth. Buff dry with another clean, soft cloth. If you want to waterproof the clean leather, apply 1 tablespoon castor oil to a soft cloth, then buff vigorously.