Coat the turkey with olive oil, and them lay it on a bed of onion, carrot and celery, skin side up. Add salt, pepper, herbs and olive oil to the bird, then 1/2 cup of water. Cover the turkey with foil. The foil and water let the turkey cook through without burning.
Fire your oven until hot, and then let the heat fall to a moderate temperature, roughly 450-500ºF. If you have fired your oven for a longer period (2 hours or more), rake out the coals to allow the temperature to keep falling. If you do not have enough retained heat in the oven, you can leave a small fire, or coals at the start of cooking.
Add the turkey to your oven, and let it roast for about 1 hour and 45 minutes to 2 hours. After about 1 hour, remove the foil, and let the turkey brown. Take the turkey out of the oven, and covered it to rest.