People have speech patterns, habitual gestures, familiar facial expressions, and characteristic ways of walking. Writers also have writing habits–favorite words or expressions that often seem apt. Maybe you like voices that rumble like thunder. Perhaps you are partial to jettison for flummoxed. Take care that you don’t over-use these darlings. Once in any short story is sufficient. Think twice before repeating them even in a book-length manuscript.
Other words aren’t necessarily favorites, just so common–so universal–that they slip in unnoticed. Probably your readers won’t notice, either. But they are so insipid that they deaden your writing. I’m talking about words like smile, frown, scowl, laugh, sigh. I’m talking about faces that flush, eyes that fill with tears.
Make a list of words that you use a lot–that you suspect that you use too often. Use the edit function of your word processing program to find each instance of each of these words. Consider which can be replaced with more precise and/or more vivid alternatives.