Blot any liquid spills from the seat as soon as they happen. Place a folded towel over the spot and press down gently to draw moisture from the fabric of the seat into the towel. Repeat with clean towels until no more liquid appears on the towel.
Rinse dried stains with cool water. Pour enough water on the seat to completely cover the stain and rub a clean towel in a circular motion over the stain. This will help refresh set-in stains and bring them to the surface.
Vacuum the seat to remove dirt and hair. While you typically remember to vacuum your carpets, you might rarely take time to vacuum seats in your home. Take off the seat cushion and use the upholstery attachments to reach into folds and cracks of the seat.
Spray stains with a spot lifter. Stain lifters are designed for use on fabrics and break down stains in the material. Scrub the stain with a small scrub brush once you've sprayed the lift onto the seat, and then allow the spot to air dry. Vacuum away the dried stain, repeating the process until the spot is gone.
Coat the seat in a layer of fabric protecting spray. These sprays use polymers to coat each fiber on the seat and repel new stains. Add just enough spray to dampen the seat, allowing it to dry completely before use.