What you needI used about 640 yards or four balls of Spud & Chloe Sweater, which works out to two skeins of color A (mine is Turtle) and one each of B and C (Moonlight and Pollen, respectively). Mine was a scrap project so the numbers aren't exact, and you will need more of C than you do of B
set of size 7 US (4.5 mm) double-pointed needles and a circular needle (or two to get a longer cable as you work)
size 7 (4.5 mm) crochet hook
Gauge is 16 stitches and 26 rounds per 4 inches/10 cm in Stockinette Stitch in the round, or 4 stitches and 6.5 rows per inch/2.5 cm.
Finished blanket is roughly 33 inches/83 cm square, but you could keep going with more yarn or additional colors to make it larger if you wanted. As is, it's a great stroller blanket.
Beginning with color A and double-pointed needles, cast on 8 stitches. Divide onto 4 needles and join for working in the round,being careful not to twist the stitches.
Knit in the front and back of each stitch. 16 stitches.
*Yarn over, knit to the end of the needle. Repeat from * to end. 20 stitches.
Repeat this round, changing to a circular needle (and adding stitch markers at the increase points if desired) when needed, until your center square is about 12 inches/30.5 cm across. (This took me 36 rounds.)
Change to color B and continue in pattern for 5 rounds.
Change to color C and continue in pattern for 5 rounds.
Change to color A and continue in pattern for 5 rounds.
Continue in pattern, changing colors every 5 rounds, 3 more times, for 4 total repeats of the stripe pattern, or 60 rounds, ending with color A. Bind off in pattern using color A.
To finish the blanket I worked one round of single crochet around the outside in color B, then one in color C and two in color A. This almost completely wiped me out of yarn, so if your blanket is any bigger you will need more yarn.
Weave in ends. For best results, wash and block before using so it will flatten out.