Sometime it’s clever not to think at all whilst sketching. Just let your hand move over the paper, canvas or whatever and see what emerges.
This is in fact what I did in this video. I left the result to the coincidence and let the creativity find its way.
I’m sure that you will be amazed about your results if you totally let go from time to time.
Hope this motivates you. If you like, send your video response and share with us what you came up with. Don’t forget: just sketch, don’t think!