In addition to your knitting needles, this pattern requires a cable needle and a tapestry needle.

The finished cowl is 22+ inches in circumference and utilizes a double sided stitch which could easily be converted to a scarf by knitting additional length and binding off instead of grafting. For a scarf of 66+ inches you will need 600 yards of the specified yarn.

Here is a link to a handy video on grafting.

This is designed for a yarn normally knit at 4 1/2 stitches per inch in stockinette.