I often need to do meditative drawing to let off stress, but I can't do Zentangles at all because it's too abstract for me. What relaxes me is drawing hair.
It started as a metaphor for mermaids without actually drawing a mermaid, inspired by art my mom used to make for me of slender ladies with lots of wild hair.
Over time I started drawing more and more hair. It's very calming to fill a page with curves and lines, and I enjoyed drawing the figures swimming in their own hair too.
I love slowly filling up the spaces with ink, breathing out along with the long lines. I also like drawing the figures first, their expressions and poses, and working their hair around that. I can choose to show the shape of the body beneath, or not.
The latest one was more personal, battered but triumphant. Drawing these lines was cathartic and purged a lot of the horror and frustration I was feeling over recent weeks.