I used a full skein of Tosh Merino Light and I really recommend this yarn if you are going to try the February Cowl - it is silky soft and has a wonderful springy/pliable quality that makes a snugly wrapped cowl easy to get on and off over your head. If you substitute a similar yarn, just make sure that it has some give to it and will hold its shape.
To make the February Cowl you will need one skein (420 yards/384 meters) of Tosh Merino Light,US 7/4.5mm circular knitting needles, scissors, and a yarn needle.
Cast on 185 stitches.
Rounds 1-3: knit all stitches.
Rounds 3-6: purl all stitches.
Repeat rounds 1-6 until you have used up your skein (or nearly so). Your cowl will measure about 6.5 inches (16.5 cm) wide when it lays flat and unstretched.
Bind off loosely.
Cut your yarn, leaving a long tail to knot off. Weave in your loose ends and enjoy!