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1. Assume They Already Like You.

Lets establish two facts first... One, we are always defensive around people we are not very much acquitted to since we don't know what to expect from them. Two, we're at least cool with people who are geniuenky interested in us. Assuming the person already likes you reduces the fear of who would be vulnerable first and the comfort shows in your body language.

2. Give Good Natural Facial Expressions.

Body language isn't just about the body like the torso, arms, posture and so on. It also include facial expressions. Good natural facial expression isn't hard to achieve. Just smile naturally when a smile is needed. Show an expression of surprise, disgust, woaw and so on when it is needed especially during conversations. It shows genuine concern and that you are really paying attention.

3. Give a Strategic Show of Vulnerability.

One other body language trick to making people like you is to give a strategic show of vulnerability. By this i mean exposing parts of your body that makes you seem vulnerable like your neck, palm, chest, abdomen, core etc. By demonstrating our own willingness to be vulnerable, we encourage such reciprocity in others.

"If you adopt the body language of a power player, it will greatly facilitate your ability to be a power player." -Nick Morgan