Shown with a cast-on count of 6 stitches.  

• Rows 1 and 37 (RS): Purl.
• Row 2 (RS): [K1, yo] 5 times, k1 (11 sts).
• Rows 3, 5, 7, 9, 11, 13, 15, 17, 19, 21, 23, 25, 27, 29, and 39: Purl.
• Row 4: K2, yo, [k1, yo] 7 times, k2 (19 sts).
• Row 6: K2, yo, k3, yo, [k1, yo, k3, yo] 3 times, k2 (27 sts).
• Row 8: K2, yo, k5, yo, [k1, yo, k5, yo] 3 times, k2 (35 sts).
• Row 10: K2, yo, k7, yo, [k1, yo, k7, yo] 3 times, k2 (43 sts).
• Row 12: K2, yo, k9, yo, [k1, yo, k9, yo] 3 times, k2 (51 sts).
• Row 14: K2, yo, k11, yo, [k1, yo, k11, yo] 3 times, k2 (59 sts).
• Row 16: K6, [k2tog, yo, k1, yo, ssk, k9] 3 times, k2tog, yo, k1, yo, ssk, k6.
• Row 18: K5, [k2tog, yo, k3, yo, ssk, k7] 3 times, k2tog, yo, k3, yo, ssk, k5.
• Row 20: K4, [k2tog, yo, k5, yo, ssk, k5] 3 times, k2tog, yo, k5, yo, ssk, k4.
• Row 22: K3, *k2tog, yo, k1, yo, k5, yo, k1, yo, ssk, k3, repeat from * (67 sts).
• Row 24: K2, [k2tog, yo, k3, yo, ssk, k1, k2tog, yo, k3, yo, ssk, k1] 3 times, k2tog, yo, k3, yo, ssk, k1, k2tog, yo, k3, yo, ssk, k2.
• Row 26: [K1, k2tog, yo, k5, yo, sl1-k2tog-psso, yo, k5, yo] 4 times, k3 (71 sts).
• Row 28: K17, k2tog, [k15, k2tog] 3 times, k1 (67 sts).