Publishers' guidelines for writers invariably place clarity on their short list of desirables. Also, learn to pack information into a sentence by using parentheses, dashes, and compound elements. Find the sentence structure that best conveys your ideas and your chosen emphasis. Choose the exactly right word and use it with precision. Don't depend on a thesaurus alone but use it in connection with a couple of good hardbound dictionaries such as Webster's New World Dictionary or American Heritage Collegiate Dictionary.
Dictionaries differ in the synonymies they choose to provide, so consult more than one.
Vivid verbs and specific nouns energize your style. A dispute over textbooks disrupted the board meeting. Prefer specific nouns and verbs to vague, general ones. Often you can eliminate adverbs and adjectives by using powerful verbs. Use technology with care.