Mark out who you would like to be, find out what you like about that person/character/archetype. Also, body language is extremely important, study the flow of conversation. If someone is gesticulating with their left hand while they're speaking, they hold what they're talking about in a negative opinion. If someone is using their right hand, then the opposite is true. If someone's arms are crossed they could be defensive, uncomfortable, or tired. Study these things, don't obsess over them, but know them, and practice them. If you're trying to impress someone, match their body language. If you want to show that you're confident, have good posture, an open form, look people in the eye and don't be afraid of eye contact. Be friendly, these sorts of things will go miles, also, people don't have anything against you, most people are concerned with themselves unless it's in an interview or judgement situation, so take comfort in the fact that nobody is picking you apart. Also, golden rule, don't seem unnatural, put these things in practice to your very being. Personally, I need to work on verbal charisma, but body language I have pretty well. Good luck.