I also thought it was pretty lucky the first time I went to look for fabric and found almost the perfect match. The fabric fades from dark to light which I also liked.
I made a garter band, and then picked up stitches along one of the long sides. Changed to stockinette with a strip of garter in the center, measuring as I went along.
Same thing for the back. The fabric was gathered and then sewn onto the knitting with elastic thread. A simple edge stitch along the neck and armholes.