Look Ma! No flippers!
The body, head, and ball are knit in the round in one piece, with the flippers knit separately and sewn on. Basic increases and decreases, as well as short rows, are used for shaping. Stitch descriptions and lots of photos are included. Finished size depends on needle and yarn size, but the example is knit on US size 3 needles with sport weight cotton yarn, and is approximately 8 inches long and 7 inches tall.