I think of my sketches as being two-colour, even thought it might be more accurate to call them monochromatic – I usually use one pen (black, more often than not) and then rely on the paper itself to act as the second ‘colour’.* Apart from making my life a bit simpler, two-colour sketches help me to focus on the design itself rather than get distracted by colour.

Another benefit of two-colour designs is that they’re great for playing with reverse colourways. It’s much easier to create a design and then incorporate its opposite.

This design reminds me of zippers or tire treads. Depending on how you look at it, it could be white on black or black on white. Even though it looks like the top and bottom parts of this sketch are in reverse colourways, they’re not; only the direction of the ‘zips’ is different.

This design could be made into a quilt pattern using half-rectangle triangles and vertical sashing, or long columns of angled strips.

* I know, I know: black and white aren’t colours. But you know what I mean.