Finishing collar on raglan sweater

i am working with size 50 needles and three strands of wool on a raglan sweater. i am at the end of the front of the sweater working towards the collar and shoulder seam. the pattern calls to leave the center 6 stitches on a stitch holder and work the remaining two sides of the stitch holder evenly attaching new yarn to the left side of the holder. HELP! cathy