You will need a mirror, some thin plywood, glue, paint and appliques or glacage. First cut your board to the size of your mirror.
I added some detail in the corner with glacage. You could also use appliques or plaster.
Once it was dry I wiped at the edges to get the paint off and create a chippy look.
This is my second stage of my living room makeover...deciding how to do the mirror above the fireplace.
For such a plain mirror, it sure is pretty now.