Scott Adams talks about this in one of his books (How To Fail At Everything). Generally, one's dress, tone, vocabulary choice, and grammar are indications of status that others read. The good news is once one is aware of it, one can fake that.

"I'm reasonably sure that my fake voice, with its low notes and artificial confidence, made me appear more capable than I was, and that wasn't difficult because I was largely incompetent at every corporate job I held. Despite my obvious lack of ability, nearly every boss I had—and there were many—identified me as a future corporate executive."