I used a 2mm hook and some of my new fave vintage cotton yarn called Coquette by Susan Crawford. It's such a wonderful yarn to crochet with.

I simply inserted my hook along the stitches at the top of the sock and made some single crochets for a couple of rows.

After I joined the third row, I made one sc, then chained 5 while skipping 3 sts. Then I did 3 sc in the next 3 sts and repeated all that from the ch 5 to the end. On the next row, I did one sc after joining the 7dc in the ch3 loop from the previous row. Then I chained 1, sc in the 2nd st of the three sc from the previous row and then another ch 1, and repeating all that to the end of the row.