For good quality apple cider vinegar, place all your apple scraps in a sterilized jar and add sugar. Fill the glass jar with water until it covers the apples and sugar, then fill to the brim. Secure the lid and shake well to thoroughly mix the sugar, apples, and water.

Remove the lid and cover the top of the jar with a paper towel, cheese cloth, or coffee filter, securing it with just the mason jar ring or rubber band. Let this mixture sit at room temperature for about 2 weeks. A dark place like a closet, pantry, or cupboard works well for this.

After 2 weeks, strain out the apple remnants, keeping only the liquid. Discard the apple pieces and return the liquid to the mason jar. Cover it again with a breathable cover such as a coffee filter or paper towel secured with the ring. Replace the filter or towel if it got wet during the transfer.

Let it sit for another 4 weeks for the second fermentation, stirring occasionally. Once done, transfer the liquid to a covered bottle for storage.