When knitting sweaters, making sure the stripes on the sleeves and body align perfectly is a real challenge. It all comes down to the type of sleeves you're working with. For raglan and set-in sleeves, the key is to match those stripes with the underarm bind off.
It's like cracking a code that gives your sweater that polished, put-together look. The attention to detail can make or break your design.
Align the stripes at the underarm shaping
Drop Shoulder or Square Armhole
Consider the drop shoulder or square armhole style: At first glance, the stripes seem to align. However, the catch is, if the model's shoulders are wider or narrower, the placement of those stripes against the body changes.