Exercise: A single figure small
Nearly two thirds of the image above is filled with a cloudy sky. I waited for a person to walk into the image on the left third, but making sure they weren't too central. The scale of the sky appears to dwarf the person further.
In contrast to the first image, the wintery photograph above consists of a dull grey sky and barren white landscape. The small reddish figure walking towards the left third of the frame is competing for attention with the large tree just off centre. If I had waited longer, until the figure was closer to the edge of the frame, then the viewers attention would have been drawn towards him against the white snow and grey foliage.