I can’t take it off so I think I’ll just have to wear it till winter comes and hope Devyn creates an ice queen outfit to get me through the winter

Susan is a "slightly built young woman"; both Mustrum Ridcully and Terry Pratchett himself have described her as being "attractive in a skinny way". Her hair is pure white, but with a streak of black running through it from end to end. Although its natural state is a frizzy mass reminiscent of a dandelion, it rearranges its style of its own accord depending on Susan's mood; it tends to form a tight bun while she is working. In The Art of Discworld, Paul Kidby draws Susan in Edwardian clothing, which he feels fits well with her job as a nanny in Hogfather.

Susan has a very striking physical presence, which both Lu-Tze and Lobsang Ludd have remarked upon, and despite her relative youth, she projects a sense of great age. In Soul Music, she complains that, as Death's granddaughter, she should have been born with better cheekbones. She also has a Look (always capitalised) which can be rather disconcerting, even to those in authority, such as her grandfather and the headmistress of the school in which she teaches.