I would say being yourself and not caring what people think of you. If you want to make intelligent changes, then make them for yourself and not so you could get someone to like you. For example, you get rejected by a girl because she only likes buff guys. You then go to a gym and try to get buff so she could start liking you. But this isn't right. You should want to get buff for yourself and not for her. There are millions of people in this world and they also have certain types and likes. If you try to impress everyone, you will go crazy. Make changes to yourself that are positive for only you and people will follow.