While removing a glued mirror, some glass shards might fall and you better lay down an old sheet or tarp beneath it.
Take duct tape and cover the entire surface of the mirror with it. This will prevent pieces of mirror from scattering if it breaks accidentally. Also remove any clips holding the mirror to the wall.
Take a piece of dental floss or picture hanging wire and make sure it is 2 to 3 metres longer than the entire width of the glued mirror. You can use piano wire or cloth fishing line as well.
Your protection is extremely vital in the entire process and you better take all the precautionary measures before performing any step further. You better wear thick gloves, long pants, heavy duty footwear and long-sleeved shirt for protecting against glass shards. Don’t forget to put on safety goggles as well.
Set your hair dryer to the hottest temperature and start heating the front of the mirror back and forth the entire surface. This will soften up the glue behind the mirror. It is better to have an assistant hold the mirror so that it does not come off the wall all of a sudden.
Take a putty knife and start prying the mirror around its edges gently. Begin from the corners and keep moving along the edges. Make sure your helper is holding on to the mirror while you loosen any glue behind the mirror.
Now slip the dental gloss or wire behind the mirror at the top. Hold one end yourself, while your assistant holds the other end and pull it back and forth to work as a saw, moving downwards gradually. You can ask for a second helper to hold the mirror so it might not fall abruptly.