Print out the parts (minus the camera case) from http://www.thingiverse.com/thing:442063.
Print out the base and lid (may need to rotate it).
Fit the webcam into the base. It should 'snap' onto the pegs.
Snap the lid on, making sure the wires go between the retainers.
Mount it onto the tilt arm.
Plug it in, tell octoprint about it, enjoy!