Snowball yarn is a soft, squishy novelty yarn composed of puffy pom-poms strung evenly on a cord. Its primary use is for scarves, although an ingenious knitter can come up with some other project for it. Knitting with any thick and thin yarn can challenge even an experienced knitter, but the construction of snowball yarn requires a special technique.
Cast on an even number of stitches using your favourite cast on method. The pom-poms will get in the way as you cast on, so just push them to one side of the needle or the other and use the cord to create your cast on row of stitches.
Knit your first stitch wrapping the cord before the pom-pom around your needle and pulling through. To make your second stitch, wrap the cord right after the pom-pom around the needle. The third stitch is the cord before the next pom-pom; the fourth is just after. You will have half the number of pom-poms as stitches hanging behind your right hand needle at the end of your row.
Continue knitting each row, starting each row with a stitch wrapping the cord before a pom-pom.
Cast off by knitting your first two stitches of the cast off row as normal and then passing the first stitch over the second. Knit your third stitch, pass the second stitch (now the first stitch on your right hand needle) over. Continue to the end of the row, leaving the last stitch live on your right hand needle.
Cut your yarn after the next pom-pom. Trim the pom-pom down with your scissors until it is as thin as the cord, pass it through the last stitch to knot it.
Weave your tail through the stitches of your scarf.