Don't waste your time or time will waste you
I do my yoga classes three times a week. And that means three times a week I have about 15 minutes to wait until training starts. And usually I'm sketching while I'm waiting. Don't like to waste my time, so, the next time I was waiting for the students in the studio, I made etchings out of my sketches. Luckily I had with me some good quality paper. Above you can spot the difference between test prints made with cheap paper and the high quality ones.
It'll be quiet here for a while because of enormous amount of work I need to do. Something like two dozens of pictures in three days.