18. This is key
People will remember not what you said but how you made them feel.
Also most people like talking about themselves so ask lots of questions about them.
19. This is how you get expert level
Always be honest so when you have to lie, people will believe you.
20. The more you say, the more opportunities for them to change their minds
In sales, (though I guess it could be applied in other ways) once you make the sales pitch, don’t say anything else.
My boss at an old job was training me and just giving me pointers. I was working at a gym trying to sell memberships. He told me that once I got all the small talk out of the way and presented the prices, that the first person to talk will lose. It didn’t seem like a big deal but it actually worked. Often there were long periods of awkward silence as the person tried to come up with some excuse, but usually they bought. It was quite impressive actually.