Shown with a cast-on count of 18 stitches.  

• Row 1 (RS): K3, yo, knit to last 3 sts, yo, k3 (2 more sts).
• Rows 2, 6, 10, and 14: K3, yo, purl to last 3 sts, yo, k3 (2 more sts).
• Row 3: K3, yo, k1, sl1 wyib, *sl1 wyib, k4, sl1 wyib, repeat from * to last 5 sts, sl1 wyib, k1, yo, k3 (multiple of 6 sts, plus 12).
• Row 4: K3, yo, k2, sl1 wyif, *sl1 wyif, k4, sl1 wyif, repeat from * to last 6 sts, sl1 wyif, k2, yo, k3 (multiple of 6 sts, plus 14).
• Row 5: K3, yo, k2, 1/1 RC, *1/1 LC, k2, 1/1 RC, repeat from * to last 7 sts, 1/1 LC, k2, yo, k3 (multiple of 6 sts, plus 16).
• Row 7: K3, yo, *k1, sl1 wyib, k2, sl1 wyib, k1, repeat from * to last 3 sts, yo, k3 (multiple of 6 sts, plus 8).
• Row 8: K3, yo, k1, *k1, sl1 wyif, k2, sl1 wyif, k1, repeat from * to last 4 sts, k1, yo, k3 (multiple of 6 sts, plus 10).
• Row 9: K3, yo, k2, *k1, 1/1 LC, 1/1 RC, k1, repeat from * to last 5 sts, k2, yo, k3 (multiple of 6 sts, plus 12).
• Row 11: K3, yo, k1, sl1 wyib, k2, *k2, sl2 wyib, k2, repeat from * to last 7 sts, k2, sl1 wyib, k1, yo, k3 (multiple of 6 sts, plus 16).
• Row 12: K3, yo, k2, sl1 wyif, k2, *k2, sl2 wyif, k2, repeat from * to last 8 sts, k2, sl1 wyif, k2, yo, k3 (multiple of 6 sts, plus 18).
• Row 13: K3, yo, k3, 1/1 LC, k1, *k1, 1/1 RC, 1/1 LC, k1, repeat from * to last 9 sts, k1, 1/1 RC, k3, yo, k3 (multiple of 6 sts, plus 20).
• Row 15: K3, yo, k2, *k1, sl1 wyib, k2, sl1 wyib, k1, repeat from * to last 5 sts, k2, yo, k3 (multiple of 6 sts, plus 12).
• Row 16: K3, yo, k3, *k1, sl1 wyif, k2, sl1 wyif, k1, repeat from * to last 6 sts, k3, yo, k3 (multiple of 6 sts, plus 14).
• Row 17: K3, yo, k4, *1/1 RC, k2, 1/1 LC, repeat from * to last 7 sts, k4, yo, k3 (multiple of 6 sts, plus 16).
• Row 18: K3, yo, purl to last 6 sts, M1L, p3, yo, k3 (3 more sts).