What do I have to do before I can start breaking it in (curing)?
Once you have put on the flue connector you can start your small and gentle fires to start the curing process. It is better to have the insulation on when you do that, but not required. Having the insulation on helps keeping the oven at a study temperature without much of a fire and the water can evaporate slowly.
Start a small fire and when the flames start touching the dome, spread the fire out and let it die down.
Keep the fires small for a couple of days, with the flame not touching the dome. You don't need a continuous fire, just a fire every hour or so to keep the dome warm. As a good rule of thumb, if you can't touch the dome with your hand, it is too hot and you need to let it cool down some.
The dome thermometer shouldn't get above 60 C or 150 F for the first 8 hours of fire. The second day the dome thermometer shouldn't get above 70 C or 160 F.
On the third day you can slowly bring your oven dome temp to 90 C or 190 F
On the fourth day, through out the course of the day, you will be able to slowly bring your oven to full temperature.
Let me know if you need anything else.