I love knitting short row sock heels! They work nicely in both toe-up and cuff-down socks. Even thought it isn't the fastest technique, I think Japanese, or pinned, short row heels are the neatest.
Like all short row heels, the heel is shaped by working back and forth in rows across half of the sock stitches. For the first half of the heel, each row is one stitch shorter than the last. For the second half of the heel, each row is one stitch longer than the last.
The big difference between the Japanese method and the other four most common short row methods (wrap and turn, yarn over, German, shadow wrapped) is that the Japanese version uses locking stitch markers, or pins, as a part of the special turning stitches.
There's more to explore in the Learning Library!