Here are some pages from one of my Notan sketchbooks showing how loose a notan painting can be. I typically try several compositions before I start to work in color. These notebooks are fairly small.
For a list of materials I use, see: Notan Supplies
Video on Notan for people who don't know the concept:
Strictly speaking the following are not notan paintings, but they serve a useful purpose in planning a painting. I use the term "color notan" to distinguish them from true notan sketches or paintings.