1) After the 1st month of use, and once per year thereafter, tighten all nuts and bolts snug to avoid loosening fasteners from the expansion and contraction experienced while cooking.
2) While storing for long periods, open the bottom draft door fully, take the top lid completely off and store under a grill cover or in a dry place like a garage or storage shed. This will give the egg proper airflow while in storage and eliminate the growth of mold on the inside.
3) Scrape all food remnants off the grill grate after each cook. Big Green Egg SpeediClean Cooking Grid Cleaner is a great product to help with this.
4) Clean the ash dump every 2-4 cooks as needed. This will help produce the airflow needed to maintain proper temperatures.
5) As needed, clean stains off the outside of the egg. Big Green Egg SpeediClean Exterior Ceramic Cleaner works great for this.
6) Each year, apply a little WD-40 to all moving parts and hinges on the outside of the egg to keep them operating freely
7) Once per year, apply a light coat of vegetable based cooking oil to the cast iron top to keep it free from rust.
8) Cook with the grill fully closed as much as possible to extend the life of the gasket. Depending on how much and how hot you cook, the gasket may need to be replaced after several years of use or after a high heat clean burn.
9) To clean the inside of the Egg, each year or as needed, run a high heat burn (over 750 degrees F) for 1-2 hours to burn off soot and grease from the inside of the dome and off the grids and conveggtor.
Check out this great video https://www.youtube.com/watch?v=gY2VynKTWtM
10) Once a year, you may need to calibrate the Big Green Egg thermometer by placing the tip in boiling water and verifying the temperature. If it needs adjusting, turn the nut on the back of the dial in order to fine tune the readout. Place in boiling water again to verify the temperature.