I have been busily quilting feathers around the edge of this customer quilt. I started by using a large platter (with pieces of tape as guides to help with positioning) and curvable ruler to mark the spine and the edge of the feathers where they don't go right up to the edge of the quilt or a change in fabric.
Then I marked 5 or 6 feathers on either side of the spine. I did this partly to see how they would fit in the irregular shapes on the inside of the spine, but mostly because I always find that I shape first feather differently, and when I get back around to it, it leaves the last feather an odd shape. So I don't actully quilt the first few I draw, and start at the third or fourth one.I basically ignore what I've drawn for the first few when I get back to them.
When I do get back to the start, I pause with space for about 5 feathers, and work out exactly how many will fit, and whether I need to adjust the sizes up or down a little to keep them looking fairly consistent (rather than suddenly finding the space remaining means that the last one is horribly skinny or really fat, and stands out like a sore thumb!).
Because I'm quilting double feathers, that means going around the quilt twice for each side of the spine. So far I've done both passes on the outside, and am still doing the first one on the inside - which is why the ones you see on the left are still single.
Once the feathered border is done, there are still some other spaces to fill, but it's getting there.