I 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.