As factors in your career success, it's not just how competent you are, and it's not just about the words you say: no less important are the non-verbal messages you send . . . and read in others. I cover some of this in my books, but let me recommend "How 'Power Poses' Can Help Your Career"– an excellent article with accompanying video from the Wall Street Journal.
The article is not–as you might suspect–about being a phony poseur, but rather about how to pay attention to the body-language and other non-verbal messages you are sending . . . and receiving.