Remove the bottom of a metal coffee can by using a hand-held or electric can opener.
Paint the coffee can black on the outside. Use Thurmalox paint or any paint that is formulated to withstand high temperatures.
Drill a hole big enough to fit the cord and light assembly into the removed bottom of the coffee can using a 3/4 inch drill bit. Paint the bottom on both sides.
Line the hole with electrical tape to prevent the sharp edges from shredding the plastic on the cord.
Run the cord for the light sock/cord set through the hole you made in the removed bottom of the can.
Place the bottom of the can, along with the cord and fixture, inside the painted can. Fix the bottom of the can in place with electrical tape.
Use the metal clamp to attach the cord to a board or other fixed surface.