Throw a piece of clothing or a length of plain fabric across a chair … and then draw two 15-minute sketches using line only with a soft pencil or charcoal.
In 5 cm squares, draw five-minute sketches of different parts of the fabric. … Identify and emphasise the areas of light and shade that will define the form.
These were drawn with a soft graphite pencil. The top four were drawn conventionally. For the bottom two, I rubbed graphite shavings from the pencil over the squares then used a putty rubber for the highlights before adding darker shadows in pencil.