New born crew sweater

Not sure what this means
The jumper has buttons on the shoulder on one side
Place front shoulder band over back shoulder band and oversee at shoulder

Sounds like a misprint or a mistranslation. Overlap the front and back shoulder bands and [I]sew[/I] in place at shoulder. If there are sleeves, the seam at the top of the sleeve will also be stitched to this overlap.