Smiling
The most effective way to seem likeable, according to the TED project website, is showing your surroundings you are happy and content to be where you are. This is why you need to smile a lot.
Listening
People tend to be somewhat egoistic, and they like people who above all listen to them. Be interested in those around you and actively listen to what they are saying.
Sense of humour
A healthy and positive sense of humour shows you are confident and original. Get on the same wavelength with people you are talking to, and do not be afraid to be funny sometimes.
Additional questions
When talking to someone, ask them supplementary questions regarding what they are saying. You will thus show you are genuinely interested in the other person and you will seem likeable to them.
Positive body language
If you show a positive attitude using body language, for example by adopting an open stance towards the other person and using positive gestures, the other person will start subconsciously mirroring these gestures and see you as more likeable.
Lack of nervousness
This might seem an odd piece of advice, but you must try not to be nervous. People feel good around another person if they can tell that person is in good mood and feels no nervousness.
Adaptation
Whenever you talk to anyone, get on the same wavelength as them and adopt their style of communication, both on the verbal and non-verbal levels.
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