Well this is my second try at getting this posted...cross your finger!
Piped binding is my favorite embellishment and its super easy to make so gather your piped binding fabric iron it flat and lets get to work!
first off you will need to cut strips that are 1 1/4 in wide and as long as you possibly can! You need to cut enough to go around you blanket plus some extra so about 180 inches. You will have extra but I'm sure you can find a project for it. Make sure to cut off selvage's.
next you are going to sew the strips together using the following technique. place one end of the fabric strip face up take another strip end and place face down on top matching up the edges like a corner of a sq see below.
You are going to sew a diagonal from one corner to the other but please make sure you do it exactly like the picture.
open it up and you get this
Trim the back seem and iron flat
Next you want to fold the strip in half and iron flat
Get your zipper foot set up
Now place the cording inside the fold as close the edge as you can.
Place under zipper foot so its right along the edge and start stitching.
On a note you will have to continually place the cording in the fold of the fabric. I usually sew about 5 inches at a time checking to make sure the cording is right up against the edge with my thumb.
You should end up with this!
You should be able to click on any of the pictures for a larger view!