Add some protection and style to your KK2 flight controller board.

Print top and bottom part of the case. For sturdiness, use 3 perimeters, 3 top and bottom layer, and 25% fill.
Apply double-sided foam tape to the bottom of the KK2 board and place it into the case bottom. This will take up any slack and prevent the board from rattling in the case.
Fasten the case top and bottom together with #4 X 5/8" wood screws; or just tape along the outside perimeters with a strip of electrical tape.
Apply double-sided foam tape to the bottom of the case and adhere it to your favorite craft.

These foam tapes works well:
http://www.hobbyking.com/hobbyking/store/_15214__Gyro_Flight_Controller_Mounting_Pad_10pcs_bag.html