Here's what you need:
Two fat quarters (or similar sized pieces of fabric)
I used all the electronics I was planning on storing as a size guideline. I cut a 12" by 12" square in each fabric.
Iron interfacing to the back of both fabrics according to directions. Heavier interfacing works best, but I used what I had and it was still pretty sturdy.
Sew around all sides with fabrics right sides together. Leave a 2"-3" opening for turning.
Clip corners & turn.
Top stitch all the way around. This adds a decorative touch and closes the opening at the same time.
Now, to make it a box. Grab each corner and fold each side on itself so that it forms a triangular point & pin. Repeat for all the corners.
I'm going to expirement with sturdier interfacing for sure. Love these boxes!