When you do smile, keep it contained - don’t break into a wide open grin. Keep your smile small and mysterious. Flash it every once in a while to keep people guessing what’s going on in that head of yours. Straight men might benefit more from smiling less, as studies show that smiling men are less attractive to women. [1] X Research source

Have excellent posture; stand up straighter than those around you. Don’t be fidgety with your hands and feet. Don’t play with your hair. When someone says something that annoys you, be expressionless and turn slightly away. Stop making eye contact. Shake hands lightly instead of hugging. Stiffen slightly when someone touches you.

If someone comes to you and asks why you were rude, gaze at him or her coolly and say you’re not sure what they’re talking about. If someone expresses sadness or anger, say “I’m sorry you were offended,” then turn around and go about your day. Using this non-apology is sure to show the other person that you are quite cold. Beware giving too many people the cold shoulder. Studies show that people who ostracize others may feel as sad as the person being ostracized. [5] X Research source

Be critical of those around you. Don’t give out compliments. If someone asks you if you like what they’re wearing, avert your eyes and change the subject. [7] X Research source

That said, if you see someone in need of real help, lose your cold demeanor and lend a hand. Think about what you’d want someone to do for you in the same situation.