So, for full disclosure I should tell you…I made this to enter a contest. A contest I didn’t win. I thought this Hidden Mickey mirror was kind of cute, though…and you might want to see how to make it, right? Right? Anyone? Bueller? 
I picked up three super inexpensive craft mirrors and used hot glue to hold them in place. Hot glue likes to pop off of smooth surfaces like mirrors so use high heat and use a lot of glue. When you’re buying the mirrors, just hold them up against each other to figure out what sizes you need. They come in a pretty wide range, so you could make this however large you would like. 
After you’ve glued together your mirrors, just start sticking on the adhesive rhinestones in the classic Hidden Mickey shape. It’s easiest to work from one edge out rather than starting in the middle. I used tiny clear rhinestones to fill in the empty spaces.
Just hang it on the wall with an adhesive hook or a piece of foam tape!