Shown with a cast-on count of 21 stitches.  

• Row 1 (RS): K1, *yo, k6, yo, k2, yo, k2tog, repeat from * (multiple of 12 sts, plus 1).
• Rows 2, 4, 6, 8, 10, 12, 14, and 16: Purl.
• Row 3: K1, *k1, ssk, k5, k2tog, k1, yo, k1, repeat from * (multiple of 11 sts, plus 1).
• Row 5: K1, *k1, yo, ssk, k3, k2tog, yo, k3, repeat from *.
• Row 7: K1, *k1, k2tog, yo, k3, yo, ssk, k3, repeat from *.
• Row 9: K1, *k2, yo, ssk, k1, k2tog, yo, k2tog, k2, repeat from * (multiple of 10 sts, plus 1).
• Row 11: K1, *k2tog, k1, [ssk] twice, k3, repeat from * (multiple of 7 sts, plus 1).
• Row 13: K1, *k2tog, yo, k1, ssk, k2, repeat from * (multiple of 6 sts, plus 1).
• Row 15: K1, *k2tog, yo, k1, yo, ssk, k1, repeat from *.