This cowl is joined at the end of each row so there will be no seam, but it is not worked in the round.
Ch 70, join without turning.
Row 1: ch2, turn, hdc in each ch across, join in top of ch2 with a sl st.
Row 2: ch 2, turn, FPHDC in each st across, join in top of beginning ch2 with a st st.
If you do not know how to FPHDC (front post half double crochet), I'm sure you can find a tutorial online, or on YouTube, but you just form the hdc in the front part of the stitch, not the top "v".
Repeat row 2 until out of yarn, or until your cowl is the desired width.
Fasten off, and weave in any remaining ends.