Shown with a cast-on count of 55 stitches.  

• Rows 1, 50, and 54 (RS): Knit.
• Rows 2, 4, 6, 8, 10, 12, 14, 16, 20, 26, 30, 32, 34, 36, 38, 40, 42, 44, 46, 48, and 52: Knit.
• Rows 3 and 51 (RS): K25, ssk, yo, k1, yo, k2tog, k25.
• Row 5: *[K2tog, yo, yo, k2tog] 5 times, k4, ssk, yo, k3, yo, k2tog, k4, repeat from * to last 20 sts, [k2tog, yo, yo, k2tog] 5 times.
• Rows 7 and 55 (RS): K26, yo, sl1-k2tog-psso, yo, k26.
• Row 9: K2, [k2tog, yo, yo, k2tog] 4 times, k5, yo, k2tog, k5, ssk, yo, k5, [k2tog, yo, yo, k2tog] 4 times, k2.
• Row 11: K24, yo, k2tog, k3, ssk, yo, k24.
• Row 13: [K2tog, yo, yo, k2tog] 4 times, k5, yo, k2tog, k2, yo, k2tog, k1, ssk, yo, k2, ssk, yo, k5, [k2tog, yo, yo, k2tog] 4 times.
• Row 15: K22, yo, k2tog, k2, yo, sl1-k2tog-psso, yo, k2, ssk, yo, k22.
• Row 17: K2, [k2tog, yo, yo, k2tog] 3 times, k5, yo, k2tog, k2, yo, k2tog, k5, ssk, yo, k2, ssk, yo, k5, [k2tog, yo, yo, k2tog] 3 times, k2.
• Row 19 (RS): K20, yo, k2tog, k2, yo, k2tog, k3, ssk, yo, k2, ssk, yo, k20.
• Row 21: [K2tog, yo, yo, k2tog] 3 times, k5, [yo, k2tog, k2] twice, yo, k2tog, k1, [ssk, yo, k2] twice, ssk, yo, k5, [k2tog, yo, yo, k2tog] 3 times.
• Row 23 (RS): K18, [k2tog, yo, yo, k2tog] twice, yo, sl1-k2tog-psso, [yo, k2, ssk] twice, yo, k18.
• Row 25 (RS): K2, [k2tog, yo, yo, k2tog] twice, k9, yo, k2tog, k2, yo, k2tog, k5, ssk, yo, k2, ssk, yo, k9, [k2tog, yo, yo, k2tog] twice, k2.
• Row 27: K13, ssk, yo, k1, [yo, k2tog, k2] twice, yo, k2tog, k3, [ssk, yo, k2] twice, ssk, yo, k1, yo, k2tog, k13.
• Row 29 (RS): [K2tog, yo, yo, k2tog] twice, k4, ssk, yo, k3, [yo, k2tog, k2] twice, yo, k2tog, k1, [ssk, yo, k2] twice, ssk, yo, k3, yo, k2tog, k4, [k2tog, yo, yo, k2tog] twice.
• Row 31: K14, yo, sl1-k2tog-psso, yo, k2, ssk, yo, k2, ssk, yo, k5, yo, k2tog, k2, yo, k2tog, k2, yo, sl1-k2tog-psso, yo, k14.
• Row 33: K2, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k8, ssk, yo, k2, ssk, yo, k7, yo, k2tog, k2, yo, k2tog, k8, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2.
• Row 35: K17, [ssk, yo, k2] twice, ssk, yo, k1, [yo, k2tog, k2] twice, yo, k2tog, k17.
• Row 37: K2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k4, [ssk, yo, k2] twice, ssk, yo, k3, [yo, k2tog, k2] twice, yo, k2tog, k4, [k2tog, yo, yo, k2tog] 3 times.
• Row 39: K19, ssk, yo, k2, ssk, yo, k5, yo, k2tog, k2, yo, k2tog, k19.
• Row 41: K2, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k4, ssk, yo, k2, ssk, yo, k7, yo, k2tog, k2, yo, k2tog, k4, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2.
• Row 43: K21, ssk, yo, k2, ssk, yo, k1, yo, k2tog, k2, yo, k2tog, k21.
• Row 45: K2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k4, ssk, yo, k2, ssk, yo, k3, yo, k2tog, k2, yo, k2tog, k4, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog.
• Row 47: K23, ssk, yo, k5, yo, k2tog, k23.
• Row 49: K2, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k4, ssk, yo, k7, yo, k2tog, k4, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2.
• Row 53: K2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k4, ssk, yo, k3, yo, k2tog, k4, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog, k2tog, yo, yo, k2tog.