Oversize artwork for less than $10. Head to your local office supply store that has an in-house print shop (i.e. Staples) and ask for a black and white engineering blueprint. Its just a matte piece of (huge) paper with ink, but the print quality is great because it has to print tiny details for architects.
Full instructions. Think of all the different ways you could make these butterflies. Cut Iridescent fabric from template, place wire in middle so you can bend in half, paint raw edges of fabric with clear nail polish or fray check. You could also take thin sheet aluminum from Home center, cut out from template, paint or glue pretty scrap booking paper onto metal.