Be clear. Clarity is the primary goal of all communication, and in business writing, the degree of transparency in one's message can determine whether one succeeds or fails in a venture, whether you're transmitting a report or closing a deal. State the intention of your message, provide the necessary details, and request the precise response you need or want.
2. Active Voice
Employ active construction (subject-verb-object). "This report was sent to me by John Smith" is not wrong, and it's probably the best choice if you want to distinguish one report from another, but consider whether "John Smith" should be the subject of the sentence; the active syntax is more vigorous, and usually more appropriate.
3. Direct Language
Construct concise, declarative statements. Your goal is to provide or invite information, or to persuade or be persuaded. Your time is valuable to you, but the recipient or recipients of your communication also have constraints and deadlines, so take the time to express yourself with economy and directness.
4. Simple Words
Favor plain, clear words and phrases over technical terms, jargon, or buzzwords. Take care not to complicate your vocabulary or stiffen your tone in an attempt to seem more businesslike or expert. By all means, use proper terminology to enhance clarity and demonstrate your knowledge and skills, but imagine how you would speak to your intended audience, and write with a conversational glossary in mind.
Strike a balance in tone that depends on the particular context of the communication. Even within categories (memos, whether in print or in email form, or marketing content), the feel of the correspondence will depend on many factors. Consult with management and colleagues, study precedents, and consider the audience when settling on the voice of a particular message.
Consider the role of a particular piece of communication. If it's summarizing a report, don't go into so much detail that the report itself is unnecessary (unless, of course, you're providing an executive summary for a company leader who doesn't have time to read it). If it's part of a larger project, match your writing style to the approach of the overall suite of materials.
Focus on the expected or hoped-for outcome. Whether you're writing to a superior or a subordinate, or to a colleague or someone outside your company or organization, be clear but courteous about the goal of your correspondence.
Avoid euphemisms or generic references; name topics outright. Diplomacy is a foundation of successful business transactions, but you can undermine success by seeming too solicitous or vague about sensitive matters. Be forthright in your discussion.
Standards for business correspondence have become more relaxed, but maintain a professional tone, avoiding slang or text-speak, exclamation points, and overly informal salutations and sign-offs.
10. Words with Friends
Be cautious about making exceptions about formality when corresponding with coworkers or associates you consider friends or confidants. Just because you dish or swear when the two of you chat in person doesn't mean you should do so in email messages or other electronic communications located on a company network. Drop the formality a notch, certainly, but don't document your lapses in professional behavior.