Choose a quality mirror.
Make a 3/4 inch plywood panel that is 6 inches larger than the mirror on all four sides.
Mount the mirror to the panel using mirror clips.
Space porcelain light bulb socket receptacles around the perimeter of the mirror using the plywood as the mounting base. Use sockets sized for standard incandescent light bulb bases.
Mark the centers of these sockets on the plywood. Drill two 1/4 inch diameter holes near this center mark for each socket.
Calculate the total wattage of the mirror lights. Add the number of light sockets and multiply by the wattage of one bulb. Sixteen 100-watt incandescent bulbs, for example, will consume 1600 watts of electricity. Use incandescent bulbs only (see Warnings below).
Wire the sockets in series. Use No.14 gauge, 2-wire-and-round electrical cable rated to handle up to 1800 watts in "load." "In series" means wiring all the sockets in a "leap frog" manner. Connect one 3-prong Edison plug to the end of a generous length of cable. From the back of the panel, thread the wire through the "entry" hole in the plywood for the first socket. Connect the wire to the three terminals (hot, neutral and ground) on the first socket. Take a short "jumper" wire and thread it through the "exit" hole in the plywood, towards the back of the panel. Connect one end of this jumper to the terminals on the first socket. Thread the free end of the jumper wire through the "entry" hole for the second socket in the series. Connect the wire to the terminal on the second socket. Run a third jumper wire from the terminals on the second socket out the exit hole. Thread this wire through the entry hole for the third socket in the series. Continue to leap frog the wiring like this until completed. All the wires should be on the back side of the plywood board. Secure any slack wiring to the plywood with gaffers tape.
Test the wiring. Prop the panel up against a wall. The sockets may "droop" a little. Put a light bulb in the first socket and plug the unit into a wall outlet. Add bulbs one at a time. Correct any wiring if a bulb does not light up, being sure to unplug the system first.
Allow all the bulbs in the unit to burn together for 1 hour. Do not let the bulbs touch any wiring or flammable material during this "load" test. If the circuit pops, you have installed too many sockets and bulbs on one wiring line. Redistribute the load by dividing the light sockets equally between two separate plug lines (see Warnings below).
Unplug the unit and let it cool until the hot bulbs can be removed.
Mount the sockets onto the plywood board with wood screws.
Build a frame that is 12 inches smaller in width and height than the plywood panel. Use 2 x 4 lumber to build this frame.
Install a number of 3 inch angle irons screwed to the inside edge of the 2 x 4 frame. Space the angle irons all around the inside of the frame on 9 inch centers.
Lift the frame up to the wall, making sure it is level. Mark the open holes in the angle irons against the wall. Drill holes and insert heavy duty wall anchors.
Hold the frame up to the wall again and drive screws through the angle iron holes and into the wall anchors. The frame should not pull out of the wall even when tugged forcefully.
Screw the panel holding the mirror and the sockets onto this wall-mounted frame.
Conceal the wiring by adding a 4 1/4 inch wide plywood facia around the panel edges.
Mask the sockets with tape and paint the unit to suit. Let dry and remove the masking.
Install the bulbs.