"Reversible binding"

I was asked how I did the biding on JoeE's quilt and since I had some of the binding left over I took a few pictures to help explain.

First I joined a 1 3/8" strip of the turquoise to a 2 5/8" strip of the navy along the long edge and pressed the seam open, resulting in this 3 1/2" wide 2 fabric strip.
Next I pressed that in half to form a folded binding one side showing only the navy, the other both fabrics.The folded strip was then attached to the back of the quilt using a 1/2 inch seam. In the picture the orange fabric represents the quilt. Pins represent the stitching line at 1/2".
Binding is then folded away from the quilt

and then wrapped around to the front and stitched down as desired.