First open up the windows and air it out as best you can. Put pans of activated charcoal around, pans of kitty litter, and baking soda in smaller areas. You might want to consider a fan to keep the air stirred up and moving, this way it prevents pocketing of musty smells.
Lovina...I like to use candles or melting pots. You can even put citrus, cinnamon and cloves on a pot and boil. Great Christmas aroma!