always look people in the eye
it's a sign of respect and confidence. if someone is speaking to you or if you pass them on the street making eye contact acknowledges that you see them. all too often people will not make eye contact and it makes me feel that they are not confident in themselves.

Smile
my mother always told me "you're so much prettier when you smile." smiling at someone can make their day. it's so easy to frown or glare - smile and project something good into the world.

Stand Up Straight
don't slouch! bad posture looks bad and makes you feel worse too!

have a firm handshake
no flimsy cold fish here! a firm handshake speaks volumes about your character. but don't squeeze too hard - someone could have arthritis and you could hurt them. just be firm and confident, show that you mean business!