Mix the vinegar with the wine and water or the beer and place in a clean bottle or wide-lipped jar. Cover with muslin and secure with string or a rubber band. Keep the jar or bottle in a dark place at room temperature.
After a few days a ‘film’ will start to form. If you can see a colour (it might be greyish) this is the ‘mother’ developing. Store for a few more weeks, then taste. If it