You'll almost surely have soot stains on the mantel and walls, "but that's better than if you let the fire burn itself out or doused it with water, which turns soot into liquid pigment," says Jeff Bishop, technical advisor for the Institute of Inspection, Cleaning, and Restoration Certification.
Vacuum up all the residue, then scrub stains using a terry-cloth towel and a nonabrasive powdered detergent mixed with warm water.
How to keep this from happening to you: Step one: Open flue. Step two: Light match. Pretty simple, really.
But the most important step is actually number three: "Always stay near the fire until the initial burst of burning newspaper has subsided and you're sure that it's drafting okay," says Grand Blanc, Michigan, fire chief Jim Harmes.
You can also light the end of a rolled-up piece of newspaper and hold it in the firebox to get the draft going.