The sweater is seamlessly knitted top-down, partly in the round and partly flat.  I recommend using circular needles, possibly changing to double-pointed needles when knitting the cuffs. 

First, the back is knitted flat until the underarms. Afterward, each shoulder is separately knitted flat on circular needles, while increasing to shape the neckline.  The shoulders are then joined to form the front yoke.  At the underarm, the front and back are joined and the body is worked in the round on the circular needles. Stitches for the sleeves are picked up along the armholes, and then knitted in the round down to the cuffs. All ribbings are knitted following a 1×1 pattern. 

Lastly, stitches will be picked up around the neckline in order to knit the folded neckband. I recommend doing this last, but you can also do this step when the body is completed.