As I explained in my previous post, I'm working on drawing the outro to Gojira's The Art of Dying. This part of the drawing will be nearly 3 meters long when finished, and consists of a pattern of repeated loops that weave together.
I do the basic linework in pencil, and then check the negative and positive shapes by quickly filling in the loops with colored pencil. It's quite painstaking work, as sometimes just a few millimeters and a slight change in the curves can drastically modify the loops.
I use a light table to trace, check, and then redraw until the loops have the right feel. Sometimes a set of loops will require a lot of trial and error. I trace a line, erase another, trace a new line, erase it.. Draw, check, erase, draw, check, erase..
I'm always looking for the right balance between the postive and negative shapes, coupled with forward-moving line dynamics and movement.