I made my own cloth leaders for a different frame but same idea. I would suggest getting a pillow ticking fabric (you know, the kind with strips in the fabric) as it makes it easier to keep them straight while cutting, sewing, and mounting. I'll bet you are excited and will end up loving the set-up!
Check this out:
http://www.justsewolivia.com/2012/09...r-longarm.html
That's the kind of fabric I used.