Since the double coin didn’t like being tied in president’s cord it seemed best to use regular satin cord and, for colour contrast, outline in black.
A common decorative technique for fancying up your knots (I like to call this illumination) is to take a cord of contrasting colour and pull it through the knot in parallel. When done with a cord of the same colour it is usually called doubling. When done with a cord (usually smaller in size) of contrasting colour, I like to call it sidelining (see right). When both sides of the cord are sidelined, then I call it outlining (see left).