ROW 4: Sc next 4 sts, drop White, join Blue, sc next st, drop Blue, pick up White, sc last 2 sts, ch-1, turn.
ROW 5: Sc next 2 sts, drop White, pick up Blue, sc next 2 sts, drop Blue, pick up White, sc last 3 sts, ch-1, turn.
ROW 6: Sc next 2 sts, drop White, pick up Blue, sc next 2 sts, drop Blue, pick up White, sc last 3 sts, ch-1, turn.
ROW 7: Sc next 2 sts, drop White, pick up Blue, sc next 2 sts, drop Blue, pick up White, sc last 3 sts, ch-1, turn.
ROW 8: Sc next 4 sts, drop White, pick up Blue, sc next st, fasten off blue, pick up White, sc last 2 sts, ch-1, turn.
ROW 9: Sc ea st across, ch-1, turn.
ROW 10-21: Rep row 4-9 2 more times. End row 21 fasten off.
With needle and yarn sew tog at short ends.