Focus on the other person, not on yourself
In an interaction, we usually focus only partly on what the other person says - the second part is focusing on what we could say next.
I think we do this for a couple of reasons.
First, we think what we have to say is really important - we want to show how intelligent we are, how much we know, and that we're superior.
Second, we want to keep the conversation going - we're afraid that we run out of things to say and that there'll be an awkward silence.
Therefore, we don't really focus on the other person but rather on ourselves. We only pretend to pay attention, but in reality, we don't.
A better way is to focus fully on the other person and forget about yourself. Even the people who appear boring on the surface have so much fascinating about them. But how could we know if we don't even try to find that out?
Treat every person as a puzzle. A mystery to be solved. What are they thinking, and why are they thinking that.
Ask open-ended questions and look deep into their eyes while nodding every once in a while. This makes them feel appreciated and important. People crave to feel important, and if you can do that for them, you're golden.
This is essentially how Lyndon B Johnson got into power. He let others shine - to be the star of the show. He never tried to influence anyone directly and gave away powerful knowledge without asking anything in return.
E.g., he helped to get one cast out senator to regain his power and even suggested him becoming the president.
Unbeknownst to everyone, Lyndon simply made allies so he himself would get to the top. He masterfully played other politicians against each other, and by the time they realized what was going, it was already too late. Lyndon was in total control.
Confirm people's self-opinion by being a deep listener. It doesn't mean you have to agree with them, but you simply understand where they're coming from. Arguing is meaningless as you're never able to change deeply-rooted opinions people have. In fact, it has the opposite effect - people resist even more. Just go find someone who has strong political views and try to change his or her mind. See how well you do.
The same applies to businesses and marketing. Companies that focus on the customer and what they can do for them are appreciated more than companies who focus on themselves and only try to get money out of their customers.
This is human nature. Everyone thinks they are more superior and more special than others. By making them feel as if they are, they become your ally as you're making them feel nobody else does.