If you are interested in something like this, check this tutorial out. There is a free downloadable butterfly template too!
Alternatively, you could go for something like this. Would you believe this look was achieved by using some coffee filters? You may need a bit of patience to make this but the end result is divine! Check out the tutorial (Note: This particular tutorial is not written in English. However, the pictures are universal and have made it easy to understand for anyone around the globe!)
Lastly, if all you want is something simple and easy to complete a particular theme, head over to this tutorial.