To make homemade vinegar which is considerably tastier than anything purchased in the store.
Use an affordable vinegar. Boxed wine still creates a product that is considerably tastier than store bought vinegar.
Some portion of wine. Either a white or a light red wine.
Unfiltered, unpasteurized vinegar.
Several Mason Jars
A stockpot large enough to do a hot water bath.
A pair of jarring tongs to remove your jars from the hot water bath.
First Sterilize your mason jars. Because of the alcohol in the wine, and then the acidity of the vinegar the likelyhood of undesirable germ contamination is low, but still possible. If all your mason jars and rings go through a dishwasher with a full heated dry cycle and you fill them while they are still hot everything should be fine.
Fill the mason jars with the wine leaving about an inch and a half of space at the top of the jar. Fill most of the remaining space with unfiltered vinegar. Then put 4 layers of cheesecloth tautly on top of the jar and put the major jar lid ring on the jar. Put the jar in a dark cabinet for a couple months and then begin tasting the vinegar every couple weeks until it no longer really tastes like wine anymore.
When you are satisfied with the state of your vinegar I would recommend sterilizing it. Sterilization is necessary if you want to pickle with your vinegar. Replace the cheesecloth on your jars with fresh mason jar lids. Put the jars in a boiling water bath with the water covering the liquid but not quite making it to ring for 10 minutes. Then remove the jars and when they are cool they are ready to use. The vinegar will be somewhat cloudy. This sediment is from the fermentation process. If you leave the jars after sterilization for some time this sediment will fall to the bottom and you can move the vinegar carefully into a new container. You will have to sacrifice a little bit of vinegar to get this clarified product. This step is only really for aesthetics, there is nothing harmful about ingesting the sediment, but the clear vinegar is very attractive.
The following steps are optional unless you want to pickle safely with your vinegar. You will need to test the acidity of your vinegar either with store bought ph strips before sterilizing it, or you can use a scale and an eye dropper. Measure out a few grams of baking soda in a small bowl on your scale. Then use an eye dropper with distilled vinegar and put a drop on the baking soda. When the bubbling completely ceases put another drop on the baking soda. Repeat until there is no bubbling at all. Note how many drops this takes. Then do the same with your home made vinegar. If it takes less of your vinegar to reach a non bubbling state with the baking soda then your vinegar is acidic enough to safely pickle with.