1st Dc in a turning row is an extended sc.

R1: Ch 32, turn. Sk 1, sc across (31)
R2: Dc 6, inc. Dc 5, inc across. Finish with 6dc. Turn (35)
R3: Sc across, ch 1, turn
R4: Dc, FpTc into Dc 2 rows below Repeat to end, finishing with 1 dc.
R5: Sc across, ch 1, turn
R6: Dc. Dc, FpTc into dc 2 rows below Repeat to end, finishing with 2 dc.

Repeat rows 3-6 (r. 7-10)
R11: sc across, turn
R12: Sc across, sc, ch 1, sc in corner. Continuing around the piece, sc to mid-point, sc, ch 5, sc in same space (this is the button loop). Continue sc to corner (sc, ch 1 sc). Sc around bottom, corner (sc, ch 1, sc). Sc up short side and join to beginning sc.

Leaving a long tail for sewing, fasten off. Fold in half, right sides together. Sew a few stitches together at the top to fasten short edges. Weave tail down short edge and sew a few stitches together at the bottom. Fasten off, Weave in ends. Sew a button on side opposite to the button hole.