First I pulled an image of a butterfly into photoshop and used the magic wand tool to delete the background white from the image. Then I connected the transparent parts of the drawing so that there were no islands. Then I exported this image as a png.
I downloaded the eps files from the candle holder instructable and opened them in Illustrator. I deleted all the inside parts. I imported my butterfly png and used the live trace function to create a vector outline of the image. Then I copied this image so that it would be on all four walls of the candle holder.
I had the candle holders cut out of 0.24" plywood at ponoko.com (it was super easy!) When they were delivered to my house I assembled them with wood glue.