I've noticed people who know what they are talking about say less words than those who don't. When you see it, you can't unsee it

They also openly admit what they don't know. And say it with as much confidence what they do know

They also tend to give great analogies that make what they are saying seem obvious. Even though it isn't

They also listen a lot longer and more often in a discussion than others do

They also can see a situation from more than just one perspective. Eg 'one way of looking at it is, the another way is this...'

Finally and this is my favourite one they summarise everything they say so beautifully. Getting to essence of their message. Over many years, I have seen this in many people and these traits have stuck with me