You pass the anchor, which of course is on the bottom, and continue until the ball, with the rode captured in the ring, slides by the boat. Needless to say, you have to be careful not to run over the rode and foul the props. Here's a tip I use to avoid that: Snap the ring tight to the ball instead of using the three-foot line.
With a long trace, the rode is three feet below the surface. But with a short trace, the ring is only a foot down, and so the rode is closer to the surface and above the level of most props.