When we're home for the holidays, I do my turkey in my Weber Kettle (charcoal fired.) You need to buy a smallish wide breasted turkey rather than a high one. Do not stuff it except you can put in a cut up apple, onion, and celery to flavor the bird.
Build a LARGE fire - when it's ready, push the coals into a ring, leaving the center open. Put a round disposable pan in the middle, top up the fire with fresh charcoal and put the turkey in the middle, breast down. Cover and roast for an hour or so.
Lift the lid and turn over the turkey, carefully with two forks. Baste if desired. Shake down the ash and top up the fire again with plenty of charcoal. Cover and continue. Top the fire at intervals until done.
The less you can open the lid, the better - but it's a delicate balance - if the coals burn down too much, they won't ignite the new charcoal.