This is a beautiful, sophisticated design for bulky yarn. Works up quickly.

The structure is worked in a unique way. The inner edge rows run perpendicular to the main design rows.

I wasn’t understanding how to work the opening rows, but I contacted the designer and received a speedy reply that cleared up my confusion.

From Ms. Chau:
The Perpendicular Cast-on is a bit different than your usual - you’ll be increasing the total number of live stitches on the needles while also creating the garter stitch edging.

Row 1: K2, kfb, turn. 4 sts.
Row 2: sl 1, k3. 4 sts.
Rather than knitting to the end of the row each time, you should be repeating these 2 rows exactly - this will create a buildup of stitches on your left needle.

So:
Row 3: K2, kfb, turn. Before you turn, there should be 4 sts on the right needle and 1 on the left.
Row 4: Sl 1, k3.
Row 5: K2, kfb, turn. Before you turn, there should be 4 sts on the right needle and 2 on the left.
Row 6: Sl 1, k3.
Row 7: K2, kfb, turn. Before you turn, there should be 4 sts on the right needle and 3 on the left.
Row 8: Sl 1, k3.

You should get a strip of garter stitch with live stitches on your needle.