Although the velvet is already lined, I'm going to use an interlining - an additional piece of fabric between the two sides of the Banner - to help support it. The velvet is quite thick and heavy, so having additional support will help spread the weight evenly and give it extra body.
As it is quite thick and heavy already, I need some quite substantial fabric for this, and have used 12oz cotton canvas. A pre-shrunk piece of the canvas (and it shrank a lot, should you ever want to use it yourself), was cut to size and edged, ready for use:
This was lined up over the back panel of the Banner, and then stitched into place. To support it properly, it needs more than just stitching round the edges, so using a strong thread and some pretty big stitches, I sewed the canvas to the seams around the central cross and between the border panels:
It's not at all easy to see in the photo, but the stiches are there, honest!
With the interlining well anchored, I folded the edges of the Banner panel over it, mitred the corners, and sewed them down with herringbone stitch all the way round:
So here's the back of the Banner, interlined and finished:
There are a few bits and pieces to do before the front can go on, but I have some time off work, so you should see quite rapid progress from here to the finish. Not long now!