Page 31 - Peter Randall "The Craft of the Knot.."

STEP 3 Tighten the knot by pulling on both the standing part and the
running end.

Twisting the ends in opposite directions will either help the belly wrap
around the spine or impede it, depending on which way they are

twisted. The Double Overhand, like all knots in the series, is very secure
and difficult to untie.

MATTHEW WALKER KNOT

This is another decorative knot that requires separating the rope you’re
working with into three strands.

STEP 1 Begin the Matthew Walker Knot by making a Wall Knot (see
further), tucking each end up through the next bight.

STEP 2 Continue by making another tuck.