Step 1: Get materials
2. a small plastic mirror. prefferably light weight and thin.
3. pen/pencil and Vis-a-Vis
5. a MacBook (not Pro)
6. Per-i-Sight template: download
Step 2: Create cardboard brackets
Step 3: Attach to MacBook
Step 4: Mount the mirror
the cardboard may need to be adjusted for imperfections in cutting. try sandpaper or X-acto. adjust the mirror and cardboard to your liking, I tried to make the template with the optimum angle and distance for maximum viewing image and angle.
ignore the line in my mirror, it's explained in the next step, which is optional.
Step 5: Trim the mirror
If you would like, mount the mirror, turn on Photo Booth and using a Vis-a-Vis mark where the tip of the pen enters the image.
draw a few lines on the mirror, slice it up, make some more cardboard brackets and tada! you have a few backups or some for your friends!