What you need is raw, unpasteurized apple cider, and the process is simple. Leave the cider to ferment on the counter. First, it will ferment into ‘hard cider’, before it turns to vinegar (2-4 weeks). You can use a few spoonfuls of raw ACV ‘with the mother’, to speed up the process. If using pasteurized vinegar, you’ll need around 1tsp of beer/wine-making ‘yeast’  to help the ferment along (don’t use bread yeast!). During the process, the mixture will bubble a lot, only ceasing once it’s ready for the ‘second ferment’. At this point, you can add in some Braggs vinegar ‘with the mother’  or a physical ‘mother’. Continue to ferment until you’ve reached your required taste, then sieve and bottle.