You can clean your sofa's fabric using a mild, water-free dry-cleaning agent or upholstery cleaner and a white cloth or rag. Using a white cloth or rag avoids transfer of dye onto your sofa's fabric from a colored cloth or rag. Follow any and all instructions and recommendations on the cleaner's container before using the cleaner on your sofa. Apply 1 to 2 tbsp. of the cleaner onto the cloth or rag then blot any stains on your sofa with the cleaner-soaked cloth or rag. Do not wipe your sofa's fabric --- this will spread the stain.
Water-free dry cleaning agents and upholstery cleaners are available at certain hardware and home improvement stores, specialty cleaning supply stores and certain retail superstores. Cleaning agents are also available for purchase online. The cleaners come in a gallon or smaller size container and do not require any catalysts or mixing of other chemicals to work properly.
After cleaning your "S" type fabric sofa using a water-free cleaner, blot the damp fabric with a dry, clean white cloth or rag to remove excess moisture. Again, do not wipe --- this will spread the moisture.
Wear latex gloves when using water-free dry-cleaning agents or upholstery cleaners to keep dirt that may be on your hands from transferring onto your sofa. Also, wear a nose mask to keep from inhaling any fumes emitting from the cleaning agent or upholstery cleaner. Work in a well-ventilated room or area and observe any warnings on the cleaner's container.