How to Write a Book Cover Prompt
A repeatable prompt recipe: genre signal, one subject, one light direction, and the title zone you need.
Say the shelf, not just the scene
Start with the category phrase a reader would recognize: literary thriller cover, cozy mystery cover, contemporary romance cover. Then describe the scene in one sentence. Without the shelf, the model produces a nice image that does not promise the right reading experience.
One subject, one light, one palette
Covers work when there is a single idea. Name the subject, the light direction and two colors, then stop. Adding five details usually produces a busy image where nothing reads at thumbnail size; if a detail matters, generate a variant with only that detail changed.
Reserve the type zone in the prompt
Ask for clear space at the top, bottom or center for the title, and say whether the title is one or two lines. If the artwork covers the whole frame, the title ends up on top of faces and windows; a reserved zone keeps the layout honest before any text is set.
Iterate one variable at a time
Keep the prompt and settings, then change one thing: the light, the palette, the subject or the type zone. Comparing two images that differ in one way tells you which choice worked. Comparing images that differ in six ways only gives you an opinion.
book cover size — A prompt can leave room for the title, but the file still has to land on the right dimensions — the size reference lists the panels, spine and bleed for each trim.