Get a mirror that has a nice frame on it, something that looks like a frame from the past. Such framed mirrors are commonly available. Next up, put the mirror face down on cardboard and apply a generous amount of paint stripper at the back. Leave it for a couple of hours and then scrape off the paint with the help of a plastic scraper. Try to get rid of most of the paint though if a small amount is left, that is fine. Clean the surface after the paint has been scraped off. Do make sure that you are wearing gloves during this process.
Apply Metal Patina Solution
Once the surface has been dried, put the mirror face down on the cardboard and start applying the metal patina solution on the reflective surface that is raw in nature. You can put more of the solutions on the edges are the point where the mirror starts aging and apply lighter coats on the inner parts of the mirror. Continue the process to the point that you are satisfied with the aged look of the mirror.
Paint the Back
After applying the metal patina solution, colour the back of the mirror once again. You can use various options but in order to give it an antique look, gold or a silver colour would probably be best. One of the techniques that is sometimes used to randomly paint the back of the mirror with dark and light silver paint though you can try this technique with the gold shade as well. Your mirror will give an excellent antique mirror effect.