Cast a sinister glow over any setting with a cluster of white tapers dripping with "blood" (actually red candle wax). Fill a cup or a small pail with sand, and plant white candles inside so they stand upright. Light a red candle and tip it over the white candles so the wax drips down the tops and sides, being careful not to burn yourself. Let wax cool completely before removing candles from sand.
Creepy Candles
Martha Stewart Living, October 2007
When I saw this idea, I retrived some old tarnished candles holders from the give away pile. It took only one red crayon to do two candles. I lit the candle, held the crayon close to the flame and the red crayon melted and ran down the candle's sides as I turned the candle holder around. It was simple and they looked great on the table at my Halloween party.
I melted a red crayon and dripped it down all the sides of a large candle. It worked great and looks very spooky.