Step 1: You Need:
Glue - any glue but hot glue. I use Aleene's Tacky Glue
Ribbon - any variety, but I prefer a less-wide grosgrain
Hole punch - or something to make holes
Decoration - any; in this instructible, I used decorative flower on wire
Step 2: Make Holes
For this set, I punched one small hole in the center (again folding in half nd punching a "half-hole" in the center).
You could also cut a pattern in your "outside" layer at this time instead of simply attaching decoartion.
Step 3: Cut & String Ribbon Ties
String your ribbon through the "inside" layer holes, crossing them.
In this set of wings, this is also when I attached the flower by pushing the wire through and laying flat.
Step 4: Glue
I prefer to use a small paintbrush for even, edge-to-edge coverage. I also paint both sides.
***Do not use hot glue. It can melt and warp the craft foam.***
Step 5: Press Layers Together
Step 6: Ta-Da!
Otherwise, once the glue is dry, you're done!