Things you'll need:
Posterboard (Black), or if you can get polypropelene sheets even better. ~$1
1 12x15" frosted cutting board (thin plastic, avaiable at most dollar stores)***
Scissors or olfa blade
Ruler & Protractor (not needed if you print out the template)
Electrical Tape (preferrably black)
Velcro with adhesive backing (or you can glue it yourself)
Optional: Glue, if you want to make tabs and glue it instead of using electrical tape
***If you can't find the clear frosted cutting board you can simply cut the same shape out of the posterboard then cut a small window in it and use tissue paper, velum, or even a cutout section of a white plastic bag.
Remember, if you like this instructable please take the time to rate it.