When you meet someone for the first time, do you put across a good impression? According to Presence, a new book by Harvard Business School professor Amy Cuddy, people assess you on two main criteria when they first meet you:1. Can I trust this person?2. Can I respect this person?Your level of trustworthiness, or warmth, is the most important factor in how people initially perceive you, Cuddy says. However, many people mistakenly believe that the second factor, characterised as competence, is more important."From an evolutionary perspective," Cuddy writes, "it is more crucial to our survival to know whether a person deserves our trust."While displaying competence is beneficial, Cuddy warns that focusing on winning people's respect, while failing to win their trust, can backfire."If someone you're trying to influence doesn't trust you, you're not going to get very far; in fact, you might even elicit suspicion because you come across as manipulative."A warm, trustworthy person who is also strong elicits admiration, but only after you've established trust does your strength become a gift rather than a threat."Cuddy also explains some of the science that can help you spot a liar.When a person is lying there are likely to be discrepancies between what they are saying and what they are doing."We're telling one story while suppressing another, and most of us are experiencing psychological guilt about doing this, which we're also trying to suppress. We just don't have the brainpower to manage it all without 'leaking'."These "leaks" can be seen in a person displaying conflicting emotions, like a happy tone of voice paired with an angry facial expression...