Details on the sizing is as follows:

X-Small: to fit bust 31 1/2”, finished bust 38 1/2”
Small: to fit bust 34 1/2”, finished bust 41 1/2”
Medium: to fit bust 37 1/4”, finished bust 44 1/2”
Large: to fit bust 41”, finished bust 48”
X-Large: to fit bust 43 1/4”, finished bust 50 1/2”

Regarding yardage: for sizes X-small and small, the pattern specifies 2 skeins each of 5 different colors; for sizes medium through X-large, the pattern specified 3 skeins each of 5 different colors. However, one of these colors is used only as a thin band of mock cables between the wider bands of color and I think you could get by with only 1 or 2 skeins at most for any of the sizes.

Regarding hook size: unless you are a loose crocheter, plan to go up a hook size or two to get gauge.

From the book:
“Like groups of heather in a garden, bands of soft color enhance this long, loose-fitting sweater. There are no crossed or twisted posts in this design, just basic stitches combined to create the illusion of cables running vertically up the sweater. Only one color and one stitch pattern is worked in each row. The body and sleeves are worked from side to side.”