1. To do or perform something (especially a magic trick) by using an optical illusion. Everyone was astounded when he appeared to levitate off the ground, but I'm pretty sure he just did it with mirrors.

2. To do something in a highly secretive, illusory, or inexplicable way, likened to that of a magic trick. The military operation was completely unseen, completely unnoticed by anybody, as if they did it with mirrors. The company's CEO managed to swindle his clients out of millions of dollars, doing it with mirrors so that no one would notice the disappearance of the money until it was too late.