The document provides guidance on how to write a summary. It explains that a summary is a short, concise statement of the main ideas and key details of a reading. To write a good summary, one should include the main idea and most important supporting details while leaving out opinions and copied text. It also should be roughly a quarter of the length of the original. The document then provides tips for summarizing paragraphs by identifying the main idea and underlining important details before condensing them into a few sentences of one's own words.