This is a wonder item, thus I am inclined to share with ya'll. The free pattern is found on therm-o-web's website and you can access it HERE if you wish.
Start with two pieces of fabric (can be the same or contrasting) that are 6 1/2" x 8". With a 6 1/4" x 7 1/2" piece of fusible fleece, line it up on the wrong side of ONE of the fabric pieces so that approximately a 1/2" gap is left on one end of the fabric. Fuse with an iron.
Now, with right sides together sew around three sides of the fabric. Leave the side with the fabric gap open. Carefully clip your corners and turn right side out. Press well and turn under the edge on the open side about 1/2". Topstitch in place, making sure edges are even.
With a ruler, mark two lines lengthwise on the fabric. One 2" from the left and the second one 2 1/4" to the right of the first one. Stitch along those lines. These are your fold lines.
Measure a piece of velcro to match the length you have left. It should be about 7 - 7 1/2". I made mine just a wee bit shorter than the fabric. Using the pictures below as a guide. Sew one piece of the velcro on the right edge, then turn the packet over and sew the remaining on on the left edge. It should now fold into place. That is, if I haven't thoroughly confused you. PLEASE check out the link at the top for more information if I have. And a huge THANK YOU to Sherry for sharing this with all of us.