How to Pit Fire Pottery and How to Build a DIY Kiln
Start by igniting your coal in one clay pot. Wait until it is ash-covered on the surface, which is when the coals are the hottest. While you are waiting, assemble the second pot. Put a layer of sawdust in the bottom. This is to insulate the pot from the heat. I use a layer of sawdust 6-8 inches deep.