Start with the decision the image should help someone make. A cover must attract interest and remain readable when small; an illustration explains or evokes an idea; a product listing must represent what buyers receive. The same attractive image can work for the first purpose and mislead for the last.
Example: introduce a fictional organizer concept with two areas. Acceptance criteria: both openings are visible, the object stands out from its background and the caption identifies a concept. We need not invent dimensions or demonstrate strength. An image selling an existing object requires checking correspondence with the actual product.
Write down the use, audience and three acceptance criteria. Then choose generation, editing, drawing, photography or a combination. This course includes preparation, selection, repair and delivery with original files. Generation services have separate accounts and conditions.