organza or some other sheer material with a higher melting point than cellophane
iridescent cellophane (I got mine in the gift wrap section of the local dollar store)
iron-on t-shirt transfer (I use the one for light fabrics by Avery)
images of butterflies to print**
parchment or other nonstick paper that won't melt (to protect your iron and your project)
newspaper to spread out if you're going to use spray adhesive in your house
E-6000 or other glue for attaching butterflies to clips
hemp cord for antennae, about 2 inches per butterfly
black polymer clay - 1/4 of a small package of Sculpey will make the bodies for 16 butterflies
solid heat proof surface (ironing boards often have a metal grid under the padding that can mess up the images)
Print the butterflies on the t-shirt transfer paper. Cut a butterfly or two from the page (it's easier to avoid bubbles if you don't try to work with the whole sheet at once), leaving some white border for now (it helps prevent the organza from fraying). Set a piece of parchment on your surface, then lay out a piece of organza slightly larger than the butterflies you cut. Place the butterflies image side down onto the organza. Iron the transfer following the directions that come with the transfer papers. Press your iron straight down on the butterfly transfer; when you need to move it to the next spot on the transfer, lift the iron up and press it straight down on the new area; you might distort the image if you slide the iron around.
Let the organza cool so you don't burn yourself, then peel the backing paper off. Set the ironed piece of organza on the newspaper. Cut another piece of organza roughly the same size as the one with the butterfly on it, and place it next to the first piece.
Take a sheet of iridescent cellophane and carefully iron it between two pieces of parchment paper until it crinkles slightly. It will shrink a little bit. Other kinds of cellophane shrink a lot (like the clear stuff I got from a floral department) but the iridescent wrapping paper type shouldn't shrink too much. Cut two pieces of ironed cellophane that are large enough to cover the butterfly. Set them on the newspaper.
Spray the organza and cellophane with adhesive. I wanted to make sure the transfer didn't peel off over time, so I made sure that the transfer side was face up and the organza face down on the newspaper. It's hard to tell since organza is sheer; pay attention to which side is which when you iron the transfer.
Pick up one piece of cellophane and carefully stick it, glue side down, on the piece of organza with the butterfly. Spray the newly exposed side of cellophane with adhesive. Stick the next piece of cellophane onto the first, glue side down. Spray the back of this piece of cellophane. Place the second piece of organza (without a butterfly) glue side down on the cellophane. You should now have a butterfly sandwich with organza on the outside. There should be adhesive on all surfaces inside the sandwich. Carefully peel the sandwich up from the newspaper. Trim the sticky edges (they likely won't line up exactly, thereby exposing some glue). Place the sandwich in between two pieces of parchment and iron to thoroughly adhere everything.
The butterfly will feel soft and flexible after ironing. You can shape the wings now, or wait until you cut out the butterfly. You can always reshape the wings by placing the butterfly back in between two sheets of parchment and ironing for a couple seconds, then holding the wings in the position you want for a few more seconds until they're cooled.
Preheat the oven to 275 degrees F or whatever temperature is specified on your package of polymer clay. Slice off a small amount (I broke off one of the four bars and used 1/16thof that bar for each butterfly body). Roll it into a short, fat snake with a taper at the tail end. Cut a piece of hemp cord about twice the length of the body you just made. Tie a small knot in each end. If you're making several butterflies, you can tie a series of knots in the cord; just make sure to leave a small space between the knots at the end of one antenna and the beginning of the next one so you can cut the cord between them. Use a thin blade to cut a slit into the head end of the clay body. Open the slit and slide the knotted cord into it, trying to keep the cord centered. Squeeze the clay around the cord to secure it. The body should now look like it has two antennae coming out of its head. Bake the bodies for about 20 minutes, or however long the package of clay specifies.
Squirt a little of the silicone glue onto the fabric body of the butterfly. Press the polymer clay body on top of it. Let the glue stiffen for an hour.
You can now glue the butterfly to the hair clip. I prefer to cut up some scraps of the iridescent fabric and glue them onto the hair clip before gluing on the butterfly. Once the glue cures (check the packaging for specifics), you can wear the butterflies.
Thanks for reading!
**Most people would probably take images from a google image search. That's understandable for personal use, but if you want to make butterfly clips to sell, make sure you're not stealing images. I've included a butterfly I drew specifically for this instructable, and I'm releasing it under the creative commons attribution license. You can sell what you make with it, but don't pretend you drew the butterfly yourself. :)
The other butterfly images I used in this instructable are also drawings I made (using Procreate on Josh's ipad). If you're so inclined, you can buy a digital copy of the pdf for those butterflies for $3. Purchasing those gives you permission to sell butterflies you make yourself with those images, but doesn't give you permission to sell or give the digital images to others.