1. USE SHORT, FAMILIAR WORDS. Vocabulary is a tool—a means to an end. It is not an
end in itself. Although a large vocabulary may be an asset, don’t “show off” with it.
Why use a large word whan a small one does just as well?
2. KEEP MOST SENTENCES SHORT AND SIMPLE. Your sentences should average less than
20 words. It is better to express a thought in several short sentences than in one long
one. Don’t worry about sounding choppy. Writers are much more aware of so-called
choppiness than readers are. Much worse than being choppy is trying to pack too many
ideas into one sentence.
3. USE ACTIVE VERBS; AVOID PASSIVES. Nothing adds more dullness to writing than the
passive voice. Write “The fullback hit the line” rather than “The line was hit by the
fullback.”
4. LISTEN TO YOUR EAR. Write what you want to say the way you would explain it verbally
in a more or less formal situation—minus the “uh’s,”“um’s,” halting and backing up,
of course. Ask yourself, “Does any of it sound phony, stilted or slangy?” If so, it
probably is phony, stilted or slangy. Try reading your writing aloud. You’ll be surprised
how well it works in helping you find problem areas. Then ask yourself, “Does this
sound like me?” The answer now should be, “Yes.”
5. GET PEOPLE INTO YOUR SENTENCES. The impersonal style, so traditional in both
school and the workplace, is hard to justify except that “it’s always been done that way.”
Times are changing. “We decided” is usually better than “It was decided.” Your reports
will be more accurate, more interesting, and easier to write.
6. KNOW YOUR SUBJECT BEFORE YOU START. Vague statements are the result of not
knowing what you’re talking about. The best way to be a good writer is to know the
subject you’re writing about. However, you don’t have to know exactly what you’re
going to say or exactly how you’re going to say it before you begin; sometimes you’ll
discover how you want to say something, and even generate a new idea or two, during
the act of writing the first, exploratory draft. If you know your subject, your assurance
and self-confidence will show through your writing. And don’t try to tell everything you
know about the subject; instead, say only what your reader needs to know or is
interested in.
Source :University of Illinois at Springfield : Six Principles of Clear Writing