Look at the sewer’s stiletto. Do you see that the point is hidden into the turned under edge. There is no sewing in that seam, yet - Remember this technique is No Sewing Until You Quilt it.
This design was very easy to stitch and quilt at the same time.
I used a zig zag stitch with invisible thread on the top and a
40 weight Rayon in the bobbin. Use the free motion or darning foot. I simply zig zag towards me, getting a stitch on both sides of the seam. Then - travel in a ditch to the center of the strip and back up with straight stitching. Repeat! All those wonderful blues were a joy to work with but hard on the eyes with invisible thread; so I had a pair of magnifying glasses made.
Also, I have discovered .005 Invisible thread by Coats and Clark, available at some Wal-Marts. My sewing machine likes this thread. You should give it a try.
I hope to be writing an article for American Quilter on joining the units of this quilt that have curved seams.
In my “No Sewing Until You Quilt It” book - on page 54, the quilt “Bloom Where You Are Planted” - You can see how I joined units with straight seams. Happy Quilting!