SOSO cardigan is worked seamlessly from the top-down. Start working the collar separately. Then you pick up as well as CO sts for the back and shoulders and shape the back neck with short rows. Continue to work the back for the length of the armhole. Pick up the stitches for the front and collar and work both fronts symmetrically for the length of the armhole. Join back and fronts to work the body in stitch pattern down to the bottom ribbing. Pick up the sleeve sts to work the sleeves in rounds.
