I am knitting a baby sweater and the pattern says "to make a 3-6 month size, start the same way, making the back about an inch wider. Sleeves will automatically be wider." So, should I do more raglan increases and then do I just measure across the back? What should the back measurement be then for a 3-6 month size? The pattern I am using is the No Seam Raglan Baby Sweater by Carole Barenys.