This is my favorite method for making homemade vinegar. Use a half or 3/4 full bottle of red wine. Place the wine in a large mouth jar or bottle, cover the top with cheesecloth and secure it with a rubber band. Leave it in a warm place, I put it at the back of my counter for 2 weeks. That's it. The natural oxidation process will turn the wine into vinegar for you! Taste it then store it in a cruet or jar with a lid.