Use headers and topic sentences to emphasize your main ideas. Readers should be able to scan your email, memorandum, or book, and understand the main points in 30 seconds or less. Understanding the main points provides your readers with the context they need to comprehend your arguments as they read more detail.
Follow your headers with definitions, wherever possible and appropriate. For example, if you are writing a section of a report about “Financial Analysis,” start that section with a definition:
“Financial analysis is the process of evaluating the value of future cash flows from the XYZ project.”
Immediately follow with a description of why financial analysis is important to the current context. Structuring information in this way helps readers who skim the section know what it is and why it is important.
Start every paragraph with a clear topic sentence that conveys the main idea of that paragraph. Readers should be able to skim your writing by only reading the first sentence of every paragraph. Ideally, your written work should be accessible for readers who have 1 minute, 5 minutes, or 60 minutes. Readers should be able to scan and absorb the big ideas without having to get into the details. If, however, they want to dig deeper into the details, they can.
Steve Levitt, successful academic and author of Freakonomics, has said that professional communication is not a suspense novel. Don’t leave your readers wondering where you are headed. Tell them your conclusion up front, and then support it with evidence and analysis.