Cold air travels down a chimney, replacing interior air that has escaped through cracks in windows and doors elsewhere in the house, seeking an equilibrium. The air rushing down the chimney picks up the smell from the creosote residue from wood fires, pushing the odour into the interior of the home. Blocking this airflow is the best way to remove the smoke smell from a wood burning fireplace.
Clean all surfaces in the room thoroughly, including drapes, upholstery, carpets and walls. Smoke can linger on any of these surfaces and contribute to the smoky smell in the room. This may not be the main source of the smoke odour, but a thorough cleaning will help ensure no odour remains.
Close the damper when there is no fire in the fireplace. This will keep the wind from travelling down the chimney, pushing the smell of smoke into the room.
Install a decorative glass door over the fireplace opening on the room side. This has the dual benefit of cutting off the smell of smoke from the chimney, but it also prevents warm air in the room from escaping up the chimney.
Install, or have a professional install, a special airtight cap at the top of the chimney flue. It is opened by a steel rod that runs alongside the flue to the inside of the fire box.