First, make sure the ingredients are chopped/grated at roughly the same size. Add them to a Ball Mason Jar (quart size). Next, fill the jar up with apple cider vinegar, and cover with a plastic ball jar lid (metal lids are corroded by vinegar). Alternatively, if you want to use a metal lid, just use a piece of wax/parchment paper between the glass and the lid. Store in a cool, dark place, shake daily (burp it to release any gasses), and store for 1 month.
Lastly, at the end of the month, strain the contents (you can compost the pulp), and jar the liquid.
Note: Some people add honey to make it easier to eat, as it can be quite strong. If using, I’d add about 1/4 cup honey, but this is optional. I enjoy it on its own as well.
Keep the fire cider in the fridge, and use 1 tsp-1tbsp at a time in a variety of uses.