Mods: I was worried about running out of the blue, so I made my shawl a little smaller. I started the edging at 211 stitches instead of 231.
Also, I was running out of the blue by the end, so I did the last two rows in the contrast color (yellow) then bound off in yellow with a purl bind off.

Note about blocking: Be sure to aggressively block every other point. I did, and they turned out lovely. The in between one will stick up while blocking, that’s fine, it will dry that way and help give it a more geometric ruffle.