Lanyard Adjuster II

This knot slides on the lanyard to adjust the size of the loop.

It is a single strand diamond knot. (4B, 3L TH knot with the ends coming out the middle of the knot)

Note: When you tie ths knot with synthetic (slippery) material the ends can work their way back through the knot causing it to collapse. A dab of glue between the ends and the knot will prevent this.
Although it is not necessary to glue the ends when tying the knot when using cotton cord you will not be remiss in doing so.

Bring working end in a bight over the standing end.

Make a second loop over the first.

Bring the working end weaving from right to left: Over, under, over, under.

Now bring working end back to the right.

Bring working end over, under two and up through center of knot.

Bring the loop of your lanyard through center of knot.

Tighten the knot.

When the diamond knot is sufficiently tight tie a constrictor knot around each end close to the knot. Trim the ends.

You could also cut the ends and add a dab of clear glue (or melt ends of synthetic material.