The recommended yarn is Shibui Staccato, a plied sock (fingering-weight) yarn that is 70% superwash Merino and 30% silk. I decided to use Manos del Uruguay Fino, a single-ply fingering-weight yarn that is 70% Merino and 30% silk.
This is a lovely yarn to knit with, not splitty and very smooth. I swatched with US 5 (3.75 mm) and US 6 (4 mm) needles.
Here are the swatching results.
US 5 washed swatch gauge: 26 stitches and 42 rows over 4 in.
US 6 washed swatch gauge: 25 stitches and 38 rows over 4 in.
Since I didn’t get gauge (24 stitches and 30 rows over 4 inches), I crunched the numbers and decided to make the next size up from my intended target. The row gauge is way off, but length is easier to tweak in a top-down construction.
The pattern starts by provisionally casting on. There is a bunch of different ways to do this: with one needle, a crochet hook, a crochet chain, two needles, etc. This time, I chose to try it this way. It was so easy, and hopefully just as easy to get the live stitches back on the needles. Here’s the beginning of the left neckband.