How does Saul Bellow use imagery in Leaving the Yellow House?

Imagery:

She was big and cheerful, puffy, comic, boastful, with a big round back and stiff, rather long legs.

And all that remained of her fine fair hair was frizzled along her forehead in small grey curls. Her forehead was not much wrinkled, but the skin was bluish, the color of skim milk. She walked with long strides in spite of the heaviness of her hips, pushing on, round-backed, with her shoulders and showing the flat rubber bottoms of her shoes.