I used other techniques described below than those written in the pattern in order to avoid having to cut the yarn at every fourth row on back-and-forth (knitted flat) parts of the sweater:

They are:
#1 mosaic stitch on the body above the underarms as well as on the shoulder caps;

#2 the two sleeves were knitted together as one with two 6-stitch steeks to cut them apart and as noted above mosaic stitch for the shoulder caps.

NOTE: If I were to knit this sweater in a larger size I would absolutely knit the sleeves in the round. In this smaller size, messing with four or five straights and keeping two colors right side up seemed worse than the choice of mosaic knitting flat with steeks.