First off, you will need a very large stock pot. I believe the one I'm using is something like 2.5-3 gallons and you can see how full it is.
1 gallon apple juice
1 gallon apple cider
3 cups sugar
8 cinnamon sticks
Combine all the above ingredients in the large stock pot. Stir well. Bring the pot to a boil. Reduce heat and simmer for 1 hour. Remove from heat and let cool to room temperature (very important unless you want to burn your house down). Add 1 liter of Everclear.
Jar or bottle up. Be careful, this is very potent stuff.