I was looking around and I got this idea from
here at the zentangle blog.
I like circles and there's something relaxing about coiled rope (it brings order to the chaos) and the way my camera takes pictures, the lighting in the room, this has a soft look. And if I added some shading, it might add some age. I'd have coils of old rope.
Anyway, I might continue and do a bit more with this picture but for now it's ok as-is.
And it's very easy to draw. Do your swirl then finish by drawing the red line.