Shown with a cast-on count of 55 stitches.  

• Row 1 (RS): K2, *yo, k1, yo, ssk, k9, k2tog, yo, k1, yo, k3, repeat from * to last 17 sts, yo, k1, yo, ssk, k9, k2tog, yo, k1, yo, k2 (multiple of 20 sts, plus 21).
• Row 2: P5, *p2tog, p7, p2tog tbl, p9, repeat from * to last 16 sts, p2tog, p7, p2tog tbl, p5 (multiple of 18 sts, plus 19).
• Row 3: K2, *yo, k3, yo, ssk, k5, k2tog, [yo, k3] twice, repeat from * to last 17 sts, yo, k3, yo, ssk, k5, k2tog, yo, k3, yo, k2 (multiple of 20 sts, plus 21).
• Row 4: P7, *p2tog, p3, p2tog tbl, p13, repeat from * to last 14 sts, p2tog, p3, p2tog tbl, p7 (multiple of 18 sts, plus 19).
• Row 5: K2, *yo, k5, yo, ssk, k1, k2tog, yo, k5, yo, k3, repeat from * to last 17 sts, yo, k5, yo, ssk, k1, k2tog, yo, k5, yo, k2 (multiple of 20 sts, plus 21).
• Row 6: P9, *p3tog, p17, repeat from * to last 12 sts, p3tog, p9 (multiple of 18 sts, plus 19).
• Row 7: K5, *k2tog, yo, k1, yo, k3, yo, k1, yo, ssk, k9, repeat from * to last 14 sts, k2tog, yo, k1, yo, k3, yo, k1, yo, ssk, k5 (multiple of 20 sts, plus 21).
• Row 8: P4, *p2tog tbl, p9, p2tog, p7, repeat from * to last 17 sts, p2tog tbl, p9, p2tog, p4 (multiple of 18 sts, plus 19).
• Row 9: K3, *k2tog, [yo, k3] 3 times, yo, ssk, k5, repeat from * to last 16 sts, k2tog, [yo, k3] 3 times, yo, ssk, k3 (multiple of 20 sts, plus 21).
• Row 10: P2, *p2tog, p13, p2tog, p3, repeat from * to last 19 sts, p2tog, p13, p2tog, p2 (multiple of 18 sts, plus 19).
• Row 11: K1, *k2tog, yo, k5, yo, k3, yo, k5, yo, ssk, k1, repeat from * (multiple of 20 sts, plus 1).
• Row 12: P2tog, *p17, p3tog, repeat from * to last 19 sts, p17, p2tog (multiple of 18 sts, plus 19).