Mix equal parts baking soda and water together in a small bowl to make a paste.
Apply the paste to the small soiled area, and brush it lightly with a soft scrub brush.
Allow the paste to dry completely, and then vacuum it away.
Sprinkle dry baking soda over the entire couch.
Brush the baking soda into the microfiber with a soft scrub brush. This allows the baking soda to reach deeper into the microfiber. Leave the baking soda on the couch for 1 hour.
Vacuum the couch to remove the baking soda and the odors it absorbed.