Tell me what you know. Be more or less specific. The passive voice is to be avoided. If you reread your work, you can find on rereading a great deal of repetition can be avoided by rereading and editing. Avoid trendy locutions that sound flaky.
Understatement is always best.
Analogies in writing are like feathers on a snake. Go around the barn at high noon to avoid colloquialisms. If any word is improper at the end of a sentence, a linking verb is. Take the bull by the hand and avoid mixing metaphors.