You will need a cable needle.

You will also need a size US 5 (3.75 mm) circular needle at least 36” (90 cm) long for the neck edge.

Finished measurements:
Chest circumference: 34.75( 38.25, 42.5, 46, 50.5, 54, 58.25, 61.75, 67)“
Finished length:

Yarn used:
Rowan Summerlite DK
Shade 466 Seashell - 4(5 ,5, 5, 5, 6, 6, 6, 7) balls