Materials

Scraps of dk yarn in 3 colours. I used a maroon tweed effect yarn for the main colour and a variegated hot pink for the contrast colour with a plain pink mohair for the scarf.
Set of 4mm dpns and a set of 3.25mm dpns
1 x 14mm (approx 1/2 inch) button

Tension

22sts and 30 rows to 10cm over st st on 4mm needles

Method

Using 3.25mm needles and contrast colour cast on 43sts and work 4 rows K1, P1 rib, increasing 1 st in the last row. (44sts)

Change to main colour and 4mm needles and work 6 rows st st.

Divide for armholes:
K7, cast off 6, K18, cast off 6, K7

Working on the last 7sts only:
1st row (WS): Purl
2nd row: K2tog, K to end
3rd row: Purl

Repeat the last 2 rows twice more and put remaining 4 sts on a holder. Work the other side (the other group of 7sts) to match, making sure to work all decrease rows as K to last 2sts, SSK

With the WS facing rejoin yarn to the middle set of sts for the back of the waistcoat and purl 1 row.

Shape for armholes as follows:
Next row: K2tog, K to last 2 sts, SSK
Next row: Purl

Repeat the last 2 rows twice more.

Neck:
With right side of knitting facing, join contrast yarn and work as follows using 3.25mm needles:
K4, cast on 4, K across back, cast on 4, K4, turn

Work 3 rows K1, P1 rib. Cast off.

Front Bands:
Using 3.25mm needles and contrast yarn pick up 18sts along one front edge and work 6 rows K1, P1 rib. Cast off. Repeat for the other side. Sew the button on one band, which side depends on your preference. On the other side make a loop (large enough to go over your button easily) with a strand of yarn, then embroider around the loop with buttonhole st.

Armhole Bands:
Using 3.25mm needles and contrast yarn, pick up 22sts around armhole and work 4 rounds K1, P1 rib. Cast off. Work other armhole to match.

Scarf
Using 4mm needles cast on 4sts and knit every row until scarf measures 30cm. Cast off and make a tassel on each end.

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