Everything matters...but whether word selection, tone of voice, movements, gestures, eye contact, etc are conscious and tortuously managed or natural and effortless is entirely dependent on who you are, and whether you need work, and how much work you need.
For some guys, just getting through a date is a Hell of 10 thousand little decisions, like playing a TV quiz show, where the grand prize is getting laid, and the consolation prize is humiliation and frustration. That's because they're playing a part they feel miscast in, like Don Knotts trying to pull off the role Rhett Butler, and trying to tame the reluctant Scarlett O'Hara.
Blame the modem world for being too soft, and breeding and accommodating boys who can reach adulthood without ever having to fight for anything. Too many spend their lives without sweat, discomfort, hunger, or struggle. No-one misses a meal. Everyone is taught to read. No-one is left out of any activity. Everyone gets a trophy. Nobody loses....except in the mating game.
The problem is men and women don't really want the same thing out of sex, no matter how socially engineered and adaptable women are to it, women are still maternal, because maternity is reproduction, and reproduction is power and eternity. Men feel the power and eternity through conquest and ejaculation. The female equivalent is childbirth, though. If every time a man had sex with a woman, he shot a 10 lb baby out of his **** that looked just like the woman he just had sex with, we might be a little more selective, ourselves.
Anyway, it really isn't rocket science, just the opposite. Either just be 100% whoever you already are, no improvement necessary, no apologies needed, and be 100% comfort in your own skin....and be happy with the type of women the who you are can attract. Otherwise, if you feel you deserve better, BECOME better....no masks, no act, just a new and improved YOU. Takes, if that's what's called for. No-one likes to hear that part. Everyone wants magic words.