If you have a wood burning fireplace, you'll need to clean it regularly. Remember to make sure that the fire is completely dead and cold before you transfer anything from the firebox to the garbage bag. Sweeping out the firebox will protect you from the possibility of re-ignited ash blowing lazily into your living room.
Beyond the basic cleaning, you'll probably want to engage a chimney sweep. A chimney sweep can thoroughly clean the inside of your chimney, preventing the occurrence of chimney fires. The sweep will also check the chimney for obstructions and leaks, the damper for anything that might hinder its opening all the way, and a number of other things that might not occur to you.
If you have a gas fireplace, cleanup is a lot easier. The following checklist is made with the gas fireplace in mind, but it can be used where appropriate for a wood fireplace.
1. Vacuum out the fireplace and heat exchange area.
2. Vacuum or sweep the log apparatus. Be careful of the vermiculite, the material used to create the look of glowing embers. It can become dislodged.
3. Clean of the logs and burners more thoroughly wherever you can see soot or carbon buildup. All you need for this is a damp cloth.
4. Check the vent to the outside (if the fireplace is direct-vent) to make sure it is free of ash, leaves, cobwebs, bird nests, and any other obstruction.
5. While you're in there, ensure that the fireplace blower is working properly.
6. Remove the glass doors carefully and clean them with an ordinary window cleaner. (NOTE: Do NOT attempt to do this until the doors are completely cool.) Do not use an abrasive cleaner or the doors will scratch and fog.
7. While the doors are out, clean the gold or brass trim with mild, soapy water. Again, do not use anything abrasive. A metal polish is not appropriate for most trim and can remove the finish.
8. Reinstall the doors and test them to make sure that they still provide a good seal.
9. If they don't, check the gasket and replace it if necessary. Otherwise, fiddle with the alignment to get the doors back on track.
10. If you see any scuff marks or scratches, remember to use an approved touch-up paint. Most paint is not sufficiently heat resistant to be used in such close proximity to fire.