Landmarks are helpful to locate ourselves as we travel through a subject's twists and turns. But what about the straightaways? How do we figure out how long a straight line is, how sharp an angle is, what the overall size of an object is, relative to another? We measure — but not with a ruler or a tape measure. We use something that lets us gauge the relative proportions from where we sit. You can use your thumb or your pen to set a benchmark. Just pin your elbow to your side, close one eye and measure the length or angle in question. Then mark it down with a little dot on the page. Turn the pen and measure the next element. Take as many measurements as you like until you feel confident.
Assignment: Pick a subject and try this measuring technique. It could be a piece of furniture, the view out a window, even your own reflection in the mirror.
Assignment: Download the PDF page of letters below, print it out, and slowly draw the negative shapes. Ignore the letters themselves and just draw what lies behind and between them.