The upholstery cleaning codes should be marked on your furniture's tags. These may be hidden from view underneath the furniture or behind a seat cushion. "W" indicates the use of water-based cleaners only while "S" indicates the use of solvent or dry cleaning detergents. "W-S" indicates that a combination of the two can be used. "X" labeled furniture should only be brushed or vacuumed. Choose your cleaner based on whichever code is on your furniture.
You should remove the surface dirt on the upholstery before you apply a cleaner to prevent the loose dirt from mixing with the cleaner and forming a film on your furniture. A soft brushing with the grain of the upholstery should lift up loose dirt. Vacuuming the upholstery with an upholstery attachment will remove the dirt and prepare the upholstery for cleaning. Examine your furniture for any spots that need to be pretreated.
Some furniture manufacturers have their own brand of upholstery spot pretreaters while others will recommend a pretreater product. Ensure that whichever product you use conforms to the upholstery cleaning codes. Test the pretreater in a hidden area on the upholstery to ensure that it will not make the color bleed. Use the pretreater according to the manufacturer's instructions, and do not soak the upholstery. Brush or vacuum up any pretreater that has dried to a powder.
Many rug steam cleaning machines have an attachment to clean upholstery that uses water-based cleaners. Test the cleaner first on a small area of upholstery to ensure that it is safe for your furniture. Follow the machine manufacturer's instructions when steam cleaning and rinsing, keeping the upholstery attachment moving so that no area is saturated. Use a cleaning solvent according to the manufacturers instructions on "S" labeled furniture, testing it first for safety.
Blot the upholstery with dry towels if some areas are damper than others to remove the excess water or solvent. If your upholstery has a nap or raised pattern on it, brush it up with a soft brush, moving with the grain of the nap or pattern. Let the furniture upholstery dry thoroughly overnight. Do not sit on the upholstery until it is completely dry to avoid matting the furniture nap or pattern.