studying jbstyle's method of drawing. www.youtube.com/watch?v=KV5tul…
if done right one can finish a clean and crispy linework within 5-10 mins from scratch without any guidelines.
the sketches took me an average of 10 mins to draw
i find it fun and mentally challenging to do as it requires a good grasp on the proportions so when you draw, all that should come out in your canvas is the image you are trying to picture out in your head.