What you will need:

1 Skull
1 Battery or 120V lamp fixture*
1 Flicker flame bulb
1 1-5 minute epoxy
Liquid latex
Red paint or pigment for dying latex
1/4 inch drill bit and drill
Wire cutters/stripers/crimpers and butt end connectors.

* These fixtures can be found at most arts and crafts stores.

The first thing you need to do is prep the skull, to do so first remove or epoxy the jaw to the skull and make sure that the skull sits flat and doesn't wobble. Once the skull is prepped, drill a 1/4 hole (or whatever size your wire requires) into the top of the skull. (see figure below)

Now take your candle's cord (if it's a 120V) and make a cut approx. 3" from the plug. If your candlestick has the cord running out of its side, try feeding the wire back into the hole and down the center of the candlestick base, this way you and your viewers will not be able to see the cord from any angle. Run the wire through the hole in the skull and out the bottom. Take the epoxy and glue the base of the candlestick to the top of the skull. If the candlestick has a felt base, you will need to remove that prior to adhering the candlesticks base to the skull.

When the epoxy is fully cured, mix up the paint and latex until you have a blood colored substance (remember that the latex will dry a lot darker than the wet mixture, so mix up the latex in a jar so you can seal it while you're testing the dried color.) Once you've acquired the desired color, cover the socket with a piece of tape and drip the latex down the sides of the candlestick. Leave it overnight to dry. You can also use real candle wax (any color), just be sure to cover the socket and try to keep the wax away from the hot bulb.

When the latex or wax are dry and set, strip the ends of the wire and re-attach the plug to the wire. Screw in the flicker flame bulb and plug it in. Your new candlestick is ready to go.