I found an intriguing brush in the little pigment shop in Venice, and decided it had to be tried. (Picture at the end of this post).
It has three brush heads on one handle so it's ideal for making even parallel lines.
Paper in this post is Bockingford 190gsm CP (NOT)
First wash of Quinacridone gold. Parallel lines of Neutral Tint and Burnt Umber painted wet on dry.
First wash of bands of Van Dyke Brown and Indigo. Second wash of parallel lines of Van Dyke Brown painted at right angles to the bands.
And here's the fascinating brush. I'm not sure I'll use it often, but its fun and effective when you want evenly-spaced lines.