How to Crochet a Face Mask, Face Warmer – video tutorial. For crochet beginner's, it will introduce the weave of simple basic: a foundation chain, single crochet (sc), half double crochet (hdc), double crochet (dc), shell, slip and horizontal puff stitches. A Puff Stitch. To crochet a puff stitch, you half-close several stitches worked in the same stitch and then join them together to finish the stitch. Size 3.5 mm (E-4) crochet hook.