Make a magic loop, sc 10 into it and tighten.
Rnd 2: 2sc into each sc around (20)
Rnd 3: sc around (20)
Rnd 4: 2sc in each sc around (40)
Rnd 5: sc around (40)
Rnd 6: sc in first sc, 2sc in next sc around (60)
Rnds 7-20: sc around.
Optional: Work 5 rounds of fpdc, bpdc ribbing.
Weave in ends and enjoy!