How to use body language to win over the people you meet.

You don’t need to read new book Captivate: The Science Of Succeeding With People to know that first impressions count. But if you didn’t know that we form an opinion of someone almost immediately, as evinced by Harvard researchers who showed study subjects two second video clips of professors teaching, then maybe you should. With only non-verbal cues to go on, participants came to much the same conclusions for 15 measures of the professors’ overall effectiveness (eg, professionalism, optimism, warmth) as those shown five- and 10-second clips. Not only that, but the two-second snap judgements matched those of students taught by the professors for an entire semester.

According to Ms Vanessa Van Edwards, human behaviour investigator and author of Captivate who also dispenses advice on such topics as making sparkling small talk and speed-reading emotions, our swift and decisive first impressions are a survival mechanism that help us assess strangers. Friend or foe? Winner or loser? Ally (not merely nonthreatening, but an enthusiastic supporter) or enemy? To become what Ms Van Edwards calls a “first impression triple threat” – in a good way – and gain people’s trust with similar alacrity, you need to deploy three non-verbal communication devices: hand gestures, posture and eye contact. Prepare to go up in people’s instantaneous estimation.

Ms Van Edwards’ own lab determined that the most-viewed TED talkers made an average of 465 hand gestures in their 18-minute monologues – almost double the amount of the least popular. (Three of them made more than 600 gestures – more than 30 a minute, or one every two seconds.) This tallies with the findings of other researchers that gesticulating job applicants were more likely to be hired. Showing your hands puts people at ease, says Ms Van Edwards, who describes pockets as “murderers of rapport” – not least because you might be concealing a weapon. Plus they disincline you from offering a handshake. So, what makes the perfect handshake? Make sure your palm is dry, the thumb is vertical, and exert pressure as if testing the ripeness of a peach. By squeezing just until you feel resistance (don’t bruise it), you release the bonding hormone oxytocin.

Your body language tells people whether you’re a winner or loser: a study showed that even congenitally blind athletes instinctively adopt postures of pride or shame, despite not seeing the impact they have. A controversial TED talk which claimed that “power posing” can make you feel more confident, increasing your testosterone and decreasing stress hormone cortisol, continues to be variously disproved and vindicated. But as numerous hapless politicians have demonstrated, standing with your legs splayed in a transparent attempt to radiate BDE will invite ridicule. Ms Van Edwards suggests instead adopting what she calls a “launch stance”: chin, chest and forehead straight ahead or up, shoulders down and back, hands visible (see above), with space between your arms and torso.

You don’t have to touch someone in order to trigger the release of oxytocin, which also fosters trust: eye contact is enough. In a YouTube video entitled “The World’s Biggest Eye Contact Experiment”, a minute of eye contact was enough to make complete strangers hug; the best public speakers address individual members of the audience and not just the back of the room, holding their gaze as well as their attention. Lack of eye contact will hinder connection with your interlocutor, but too much will weird them out: the scientifically located sweet spot is between 60-70 per cent. (We make 41 per cent when talking and 75 per cent when listening.) Nailing the exact percentage is less important than not looking over their head for someone more interesting, the bar or the door.

Captivate: The Science Of Succeeding With People (Penguin) by Ms Vanessa Van Edwards is out now