Instructions:
Using 4 mm needles, cast on 28 stitches in double knit edge colour
Purl 1 row
Knit 1 row
Change to main colour
Starting with a Knit row continue in SS and work 12 rows.
(K1, K2tog) rpt to end K1 (19st)
(P1, P2tog) rpt to end P1 (13st)
(K1, K2tog) rpt to end K1 (9st)
(P1, P2tog) rpt to end (6st)
Knit. Continue in SS
Inc in every stitch (12st)
Inc in every stitch (24st)
Purl two rows
Cast Off

Making Up:
Over sew the row ends, turn right side out. 
Make a twisted cord in the contrasting edge yarn and tie this around the neck of the sack to finish.