Shown with a cast-on count of 39 stitches.  

• Rows 1, 3, 5, and 7 (RS): K3, [ssk, yo] 3 times, k1, *[yo, k2tog] twice, yo, k3, k2tog, ssk, k3, [yo, ssk] twice, yo, k1, repeat from * to last 10 sts, [yo, k2tog] 3 times, k4.
• Rows 2, 4, 6, 8, 10, 12, 14, 16, 18, 20, 22, 24, 26, 28, 30, and 32: Purl.
• Row 9: K2, [k2tog, yo] 3 times, k3, yo, [ssk, yo] twice, k2, ssk, k2tog, k2, yo, [k2tog, yo] twice, k3, [yo, ssk] 3 times, k3.
• Row 11: K1, [k2tog, yo] 3 times, k5, [yo, ssk] twice, yo, k1, k2tog, ssk, k1, [yo, k2tog] twice, yo, k5, [yo, ssk] 3 times, k2.
• Row 13: [K2tog, yo] 3 times, k7, [yo, ssk] twice, yo, k2tog, ssk, yo, [k2tog, yo] twice, k7, [yo, ssk] 3 times, k1.
• Row 15: K1, [yo, k2tog] twice, yo, k3, k2tog, k4, [yo, ssk] 3 times, [yo, k2tog] twice, yo, k3, k2tog, k4, [yo, ssk] 3 times.
• Rows 17, 19, 21, and 23: K1, [yo, k2tog] twice, yo, k3, k2tog, ssk, k3, [yo, ssk] twice, yo, k1, [yo, k2tog] twice, yo, k3, k2tog, ssk, k3, [yo, ssk] twice, yo, k1.
• Row 25: K2, [yo, ssk] twice, yo, k2, k2tog, ssk, k2, [yo, k2tog] twice, yo, k1, k2, [yo, ssk] twice, yo, k2, k2tog, ssk, k2, [yo, k2tog] twice, yo, k2.
• Row 27: K3, [yo, ssk] twice, yo, k1, k2tog, ssk, k1, [yo, k2tog] twice, yo, k2, k3, [yo, ssk] twice, yo, k1, k2tog, ssk, k1, [yo, k2tog] twice, yo, k3.
• Row 29: K4, [yo, ssk] twice, yo, k2tog, ssk, [yo, k2tog] twice, yo, k7, [yo, ssk] twice, yo, k2tog, ssk, [yo, k2tog] twice, yo, k4.
• Row 31: K3, [ssk, yo] 4 times, [yo, k2tog] twice, yo, k4, ssk, k3, [yo, ssk] 3 times, [yo, k2tog] twice, yo, k5 (40 sts).