While we were traveling, I made about 22 index cards... here are some of the cards. I worked on them on the flights, on a bus ride, in the hotel room. The cards in this post are ICADs #26-37.
Did a bunch like this, just practicing the alphabet over and over again.
I had painted some backgrounds with gouache before we left, and I also drew on cards stained with tea. These cards were drawn with a Kuretake brush pen.