Shown with a cast-on count of 20 stitches.  

• Row 1 (RS): K20.
• Row 2: K2, yo, purl to last 2 sts, yo, k2 (22 sts).
• Row 3: K2, (k1, yo, k1) in next st, *yo, k1, repeat from * to last 3 sts, (k1, yo, k1) in next st, k2 (42 sts).
• Row 4: K2, yo, purl to last 2 sts, yo, k2 (44 sts).
• Row 5: K2, (k1, yo, k1) in next st, k2, *k3, k2tog, k4, yo, p2, [k2, yo, ssk] 3 times, p2, yo, k4, ssk, k3, repeat from * to last 5 sts, k2, (k1, yo, k1) in next st, k2 (48 sts).
• Row 6: K2, yo, k5, *p2, p2tog, p4, yo, p1, k2, [p2, yo, p2tog] 3 times, k2, yo, p4, p2tog, p3, repeat from * to last 7 sts, k5, yo, k2 (50 sts).
• Row 7: K2, (k1, yo, k1) in next st, k5, *k1, k2tog, k4, yo, k2, p2, [k2, yo, ssk] 3 times, p2, k2, yo, k4, ssk, k1, repeat from * to last 8 sts, k5, (k1, yo, k1) in next st, k2 (54 sts).
• Row 8: K2, yo, k8, *p2tog, p4, yo, p3, k2, [p2, yo, p2tog] 3 times, k2, p3, yo, p4, p2tog, repeat from * to last 10 sts, k8, yo, k2 (56 sts).
• Row 9: K2, (k1, yo, k1) in next st, k8, *yo, ssk, k2, yo, ssk, p2, yo, k4, ssk, k6, k2tog, k4, yo, p2, k2, yo, ssk, k2, repeat from * to last 11 sts, k8, (k1, yo, k1) in next st, k2 (60 sts).
• Row 10: K2, yo, k11, *yo, p2tog, p2, yo, p2tog, k2, p1, yo, p4, p2tog, p4, p2tog, p4, yo, p1, k2, p2, yo, p2tog, p2, repeat from * to last 13 sts, k11, yo, k2 (62 sts).
• Row 11: K2, (k1, yo, k1) in next st, k11, *yo, ssk, k2, yo, ssk, p2, k2, yo, k4, ssk, k2, k2tog, k4, yo, k2, p2, k2, yo, ssk, k2, repeat from * to last 14 sts, k11, (k1, yo, k1) in next st, k2 (66 sts).
• Row 12: K2, yo, k14, *yo, p2tog, p2, yo, p2tog, k2, p3, yo, p4, p2tog, p2tog, p4, yo, p3, k2, p2, yo, p2tog, p2, repeat from * to last 16 sts, k14, yo, k2 (68 sts).
• Row 13: K2, (k1, yo, k1) in next st, knit to last 3 sts, (k1, yo, k1) in next st, k2 (72 sts).
• Row 14: K2, yo, knit to last 2 sts, yo, k2 (74 sts).