There is tutorial to make an origami butterfly going around on pinterest, and while it looks pretty simple there might be a few missing steps. Since I'd already started to fold my butterfly, and was determined to make it happen, I looked around and found a tutorial that made sense to me.
The butterfly is a terrific origami project for fabric because it is made with just one square. Some origami projects use multiple pieces of paper. I started looking at how to fold origami flowers and some of them use 60 sheets of paper! That would be totally unreasonable with fabric. It would take f-o-r-e-v-e-r, and would probably be too bulky to fold.
If you want to make these, you might practice folding one with paper first. You do need to have some accuracy with the folds, and a trial run you will get the feel for how it works. Then you can keep the paper version to use as a visual reference while folding the fabric ones. Use paper with two different sides--either print, color, or texture.
Below is a diagram showing the size to make the fabric piece. You can make it any size, but 4.5" x 6" is easy to fold, and the butterfly turns out a nice size for a pin or embellishment (4" at widest point x 2.75" tall). To make it other sizes, decide on a height and then make the width about 75% of the height (height x 0.75).
My butterflies are dupioni silk for one side and cotton lawn for the contrast. It is just the fabric--I didn't use interfacing. If you want to use interfacing, this is a project where a lightweight NON-woven interfacing would be perfect.
I sewed the pieces together using a 1/4 allowance, turned them right side out, and slip stitched the opening closed. On two of them I topstitched around the perimeter, and I think it made them easier to fold. The topstitching adds some stability to the fabric. Plus, you know I never miss an opportunity to topstitch!
After you make a fabric piece, go to these instructions and start at step #4. The instructions are for paper, and since origami paper is usually square, the first few steps are for cutting the paper into a rectangle. If you are making it from fabric and want your raw edges enclosed, cutting it down isn't an option. So make your fabric piece as described above and then start at #4.
At the end, I slip stitched the wings down to hold the folds together nicely.
Happy fabric folding!