When I’m knitting socks for myself, like the Cubicle Socks Trio, short row heels are my favorite. They’re worked the same whether you’re knitting your sock from the top down or the toe up.
The general idea is for the first half of the heel, each row is one stitch shorter than the last and ends with some sort of special turning stitch. The rule of thumb is that about 1/3 of the heel stitches on each side are turning stitches and 1/3 of the stitches at the center are plain stockinette stitches. Then for the second half of the heel, each row is one stitch longer than the last and the turning stitches are worked to prevent any holes at the ends of the rows.
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