Cast on 42 sts.
Work 4 rows in Garter st (k every row).
Next Row (RS): Knit.
Continue in St st (k on RS, p on WS) until piece measures 12 in. (30.5 cm) from beg.
Work 4 rows in Garter st.
Next Row (Shape flap): K2tog, k to end.
Rep last row until 6 sts remain.
Button loop: Bind off 4 sts. Work remaining 2 sts in
Garter st for about 1 in. (2.5 cm). Bind off.
Cast on 160 sts. K 2 rows. Bind off loosely.
Fold lower edge of bag up about 6 in. (15 cm) and seam sides. Sew Strap to Bag. Sew end of button loop to flap. Sew on button. Weave in ends.