Either by looking at him or while talking to him?
Most Helpful Girl
If a guy walks up to you, chatting you up, that's a dead give away even though he might be nervous as hell inside. He still had the confidence to walk up to us and say hello.
His voice isn't high pitched nor does it waver. He's speaking calmly, he's not jittery or twitching, so that doesn't give off any nervous vibes.
I've noticed--and this means nothing overall--that confident men walk straight-backed, arrogant men walk with a sort of sway, and men who lack confidence walk with a sort of defeatist pose (slightly hunched over). It could be a multitude of other things though.0