Shown with a cast-on count of 20 stitches.  

• Round 1: K1, p2, *k2, p2, repeat from * to last st, k1.
• Round 2: Ssk, p1, [k2, p2] 3 times, k2, p1, k2tog (18 sts).
• Round 3: K1, p1, *k2, p2, repeat from * to last 4 sts, k2, p1, k1.
• Round 4: Ssk, [k2, p2] 3 times, k2, k2tog (16 sts).
• Round 5: K1, [k2, p2] 3 times, k2, k1.
• Round 6: Ssk, k1, p2, k2, p2, k2, p2, k1, k2tog (14 sts).
• Round 7: *K2, p2, repeat from * to last 2 sts, k2.
• Round 8: Ssk, p2, k2, p2, k2, p2, k2tog (12 sts).
• Round 9: K1, p2, k2, p2, k2, p2, k1.
• Round 10: Ssk, p1, k2, p2, k2, p1, k2tog (10 sts).
• Round 11: K1, p1, k2, p2, k2, p1, k1.
• Round 12: Ssk, k2, p2, k2, k2tog (8 sts).
• Round 13: K1, k2, p2, k2, k1.
• Round 14: Ssk, k1, p2, k1, k2tog (6 sts).
• Round 15: K2, p2, k2.
• Round 16: Ssk, p2, k2tog (4 sts).
• Round 17: K1, p2, k1.
• Round 18: Ssk, k2tog (2 sts).