Vacuum all parts of the sofa, including beneath the cushions, with an upholstery attachment.
Fill the carpet cleaning machine with the appropriate amounts of water and detergent.
Apply the cleaning solution sparingly to the sofa and cushions. Use the upholstery brush to gently scrub the fabric. Pull the attachment backward without squeezing the trigger to remove the moisture as you go.
Allow the sofa to dry completely before putting the cushions back in place.
Vacuum the sofa and cushions thoroughly.
Hold the can of carpet cleaner upside down and spray onto the sofa and cushions.
Allow the cleaner to remain in place for the recommended amount of time.
Remove the cleaner from the sofa with a dampened sponge. Use a blotting motion to avoid rubbing loosened dirt back into the fabric. If it still feels very damp, blot with a dry cloth to remove excess moisture.
Replace the cushions after all parts of the sofa are dry.