Build a fire in the oven. Pile charcoal on the floor of the even in the shape of a pyramid. Crumple a few pieces of newspaper and position them around the base of the charcoal pyramid.
Ignite the fire. Strike a long matchstick and press the flame against the pieces of crumpled paper. The paper should catch fire and spread to the charcoal. Allow the oven to heat for two to three hours.
Remove the hot coals with a wrought iron shovel. Use a broom with a wrought iron handle to sweep away any debris and ash on the floor. Wear protective, heat-resistant gloves while removing the coals, ashes and debris.
Let the oven sit for about an hour to let the heat even out.
Set whatever item you are cooking in its cooking vessel and place it on the floor of the oven. For example, if you are cooking a pizza, set the prepared pizza on a pizza paddle and slide it into the oven. Once cooked, slip the paddle under the pizza and remove it from the oven. If cooking in pots and pans, set them on the floor of the oven.