The crown knot is a very useful knot to keep the end of three stand rope from fraying. This knot is actually very easy to tie.
It is best to look down at the knot while tying it. I always orient the knot in an anti-clockwise direction so that it will tighten the lay of the line as it holds.
The crown knot finishes with the tails aiming back into the rope, where as the wall knot finishes with the tails aiming away from the rope. The tails are then poised to be tucked back into the line to complete the backsplice.
The crown knot will untie if the tails are not seized into a splice or other knot, making this knot rather weak when used alone to hold the end from fraying; but when used in combination with a splice, it will hold the line securely and can be used as the permanent termination to the line.