Gauge
24 stitches and 32 rows = 10 cm
over stocking stitch using 3.75mm needles

Measurements
To fit chest
35 40 46 cm (14 16 18 in)
Length from back neck
24 28 28.5 cm (9½ 11 11¼ in)
Sleeve seam
12.5 14 15 cm (5 5½ 6 in)

Each source has a different set of recommended yarns. The following is from the King Cole version.

Materials
King Cole Baby Big Value DK
2 2 2 100 gram balls
King Cole Soft as Silk DK
2 2 2 100 gram balls
1 button.