Clean the couch to remove built-up dirt and stains; it will instantly improve the appearance.
Cover the couch with a custom-made or store-bought slipcover to give it a new look. Save money with a custom piece by having a slipcover made only for the seat cushions, the most worn part of a couch. Choose a fabric that is tightly-woven, durable and machine-washable. Weigh the cost of fabric plus labor to make a custom slipcover -- which can be a minimum of $400 just for labor -- against the cost of a new piece of furniture.
Reupholster the couch with new fabric. Enlist the services of a professional for a job that will last.
Accentuate the best your clean couch has to offer with new decorative pillows and a throw.