Split evergreen wood into pieces no larger than about 3 inches in diameter.
Let the wood dry for at least a year in a well-ventilated space that's protected from the elements. Evergreen wood takes a long time to dry, and some pockets of sap never completely dry, which accounts for the popping noises as they heat up and turn to steam. If the wood is wet when it's burned the heat output will be much lower.
Use evergreen wood for the initial kindling to start the fire. Evergreen wood catches easily and burns very hot, which allows other woods to also catch fire.
Avoid filling a firebox completely with evergreen wood. The fire may become so hot that you run the risk of starting a chimney fire. A good ratio is two pieces of alternate wood for every evergreen piece. Oak and other hardwoods make good matches for evergreen, with the evergreen providing a quick, hot fire and the other wood offering a longer, steady flame when the evergreen burns out.