Step 1. Know your audience.
Are the advertisements during the Super Bowl the same as the ones played during soap operas? Do you tell your parents the same details about your weekend that you tell your best friend? Intuitively we know the importance of adapting our message to our audience, yet when we sit down at our keyboards we seem to forget that as writers we also have an audience.
Keep in mind that a key writing principle is to adapt your message to your audience. Consider the level of understanding of your readers. Are they familiar with your topic, or do you have to spend more time providing background information? Consider word choice and vocabulary to enhance the connection to your reader. What are their expectations and preferences? What do they hope to get from your message? If you ask these questions, you will anticipate your readers' questions and make sure to include the necessary details. In the long run, this is both satisfying to your reader and cost effective.
Arrangement is important too and is related to audience. One of the most important audience-centered considerations is their likely reaction to your message. Four basic reactions are possible: neutral, happy, unhappy, or "what's in it for me." If your message is likely to be received as neutral or happy news, you can start with your main point. (Remember your college acceptance letter began with "congratulations.") If you're writing a bad news message, and your audience is likely to be unhappy, start with the rationale for the decision or the explanation. If you place the main point (bad news) in the first sentence, your reader is unlikely to carefully consider your reasons. Place the actual bad news in the middle of a paragraph, and use a complex-compound sentence to lessen the impact and deemphasize the negative tone. If you have a persuasive message (what's in it for me), engage your readers with why they should care; follow-up with the key selling points and include the benefit to the readers. Finally, request action. (This is the recipe for a cover letter!)
Today you can take the first step towards becoming a better writer. Envision your specific reader as you compose your message. Kurt Vonnegut offers the following advice on audience: "Write to please just one person. If you open a window and make love to the world, so to speak, your story will get pneumonia." Imagine what you will catch if you write as if you don't even know who your audience is.