You must knit the hemline in one piece. Sides are seamless. You knit 140 full cardigan stitch for 20 cm. When you come to under-arm; You must mark 35 loops for the right front, for the back part 70 loops and again, for the left front 35 loops. You cast off 10 stitches for each under-arm and continue knitting. To make a V-Collar you must decrease 1 stitch from the collar edges.
When you have 18 cm. from under-arm, you must cast off 20 stitches for the shoulders, and 35 stitches for the back at one time, and finish. Only the shoulders will be stitched. With a dark blue yarn, all the edges will be crocheted as in the picture. You can crochet the first letter of the baby with single crochet and stitch to the vest.