What headings and subheadings of the body of an outline should be?

The headings and subheadings of the body of an outline should clearly reflect the main topics and subtopics of the content being organized. Each heading represents a major idea or section, while subheadings break down those ideas into more detailed components. This hierarchical structure helps ensure logical flow and clarity, making it easier for readers to follow the argument or narrative. Additionally, using consistent formatting (like numbering or bullet points) can enhance readability.