Rub the entire surface of the suede sofa or couch with the suede brush. This helps lift up the "nap" of the suede so that you can clean it properly. You can also use a dry towel or rag for this purpose.
Use a suede bar to clean stains on the surface of the couch---it acts as a stain eraser. Rub the bar back and forth along the stain to lift it from the fabric.
Brush the stain with your suede brush again to remove the leftover residue from the surface. Brush it off the couch with your hands if necessary.
Dampen a cloth towel with a bit of white vinegar and use it to remove or loosen stubborn stains on the surface. Try this solution in a small area first to ensure that it doesn't damage the color or fabric before using it in other sections of the couch or sofa. The vinegar smell goes away after drying.
Use a leather conditioner designed specifically for suede if you have grease stains on the couch. Spray on the solution and wipe the surface with a cloth per the instructions.