Isn't it strange that some people speak so less but are so convincing with people whereas others have to do so much work and tell so many stories and examples for the same result? Conviction in a person is nothing but trust in that person. And the more we trust someone, the lesser the information we need from them to believe what they are telling. One the other hand, the lesser the trust we build with someone, the more the information and facts and figures and proofs we need to provide to convince them of our point of view.
One needs to decide the approach they want to take. Work on collecting data and facts or work on building themselves, their personalities and their non-verbal and verbal communication in a way that trust becomes implicit. The latter is an easier, more long term approach. Here are some things I have found are needed to build trust:
1. Positive pure vibrations that we send out to people - when we meet people we are very friendly on the outside but what are we thinking on the inside. When we don't genuinely see the good in people, whether we show it or not, it goes across to them through a sixth sense that we all have.
2. Common bonds - human relationships are very much like the covalent bonds we study about in chemistry. A single bond is weaker than 2 bonds which are weaker than 3 or 4 and so on. These covalent bonds in the case of people are common things we have between each other. You and I could both love cars or we could both love travelling to the beach or we could both have a son and a daughter or we could be both from the same state or city or went to the same school or got married in the same year or were in the same city at the same time or whatever common can be among a zillion things possible. The more then common things we find between us, the more we have the "me too" experiences, the more the trust between us. And how does that happen? When we are focussed on making the other person talk more than we talk.
3. Becoming a genuine fan of the other person - most people in the world are poor in one area of life - having enough people to listen to their story of life. Everybody is so busy talking about their problems and their points of view that there is no time to listen to the other person. True undisturbed listening is almost cathartic. Whenever I am with somebody I am just looking to know more about them and how they happened to reach here in their life. Regardless of where one is in life, they have created some massive victories in their life to reach where they are. Walked to school on feet, took a loan to study, overcame a broken household, went through the trauma of failing multiple times or losing a loved one and so on. And when I get them to tell me about their story, one thing almost always happens - I become a true fan of theirs for what they did in their life. I really believe that in similar circumstances I could not have done better.
And once trust is established, it's a matter of a few sentences to get your point across to the other person.