The whip stitch is very useful for putting hems on finely knit items like t-shirts or soft pants. Because fine knits are difficult to unravel, you don’t need to fold over the edge twice, you can stitch over the cut edge, which also gives the hem a lower profile. If you are hemming a ribbed knit, lining up the ribs helps keep the fabric even and gives a nice gauge for stitch size!

I started at a seam, and hid the thread knot in the seam fold. Then I put the needle through the pearl side (indent) stripe on the inner layer, and just picked up a couple loops on the next rib of the outer layer. To keep the stitches at the right tension, after stitching a few I pulled open the ribbing to draw in the thread. This leaves the stitches loose so they won’t show and are less likely to snap when the fabric stretches. Pulling the stitches tight would result in a visible stitch line that would break the first time the fabric stretched.