I used the Round Heel for James sock. Here's a close up.
To turn a round heel, the initial row is knit to 2 stitches past centre. In the case of James socks, centre was between stitch 14. I knit to centre (14) plus 2 - or 16 stitches, before making a decrease to start the turn.
The socks look good so far and are knitting up quickly.