Da Vinci said, ” Sketch quickly with light strokes on your pad (which you should always have with you), and when it is full, start another, never rubbing out but keeping all carefully, because the forms…….are so infinitely various that they cannot possibly be retained in memory. Therefore preserve your sketches, for they are your assistants and your masters.”
The first thing to gleam from this quote is how important it it to keep a sketchbook. It is our practice place, a place to experiment with techniques & composition,and also to preserve visual lines and ideas. As Da Vinci says it is useful to use as your assistant for bigger art projects. The next idea from him is to use a quick light touch with your strokes, never over thinking the process. You force the right side of your brain to work at noting relationships between the spaces and lines. He also points out that you should leave all the lines, even the ones you want to erase! I tend to like to sketch with a black, thin, ink pen which you can’t erase but just need to work with. It’s a good exercise in creativity too, what to do with that weird line you drew. So get out a sketchbook as Da Vinci says and carry it with you always and get sketching!