You can start using the Tandoor straight away. We suggest not to make naan bread until Tandoor has been used twice (burnt for approx. 6 hours in total).
After first use, add 1 tablespoon of salt in 2 liters of luke warm water. Dip a cloth in to it, & squeeze all the access water. Use the cloth & go thru the clay walls as if you are moping it. Do it gently, don't use any force.
Little bit of clay would stick to the cloth. Don't worry..
Leave it to dry.
Use Tandoor as normal the second time (doesn't have to be straight away), but don't use it to make make naan bread / tandoori roti yet.
Your Tandoor will be ready for making Naan bread after your second Tandoori session..