One distinction I have always found interesting, is that a large portion of Ni-doms are quite self-aware individuals (disregarding the correctness of their self awareness; that's another matter). Yet, Ni is inheriently anti
-self aware. I like describing it as going "from A, to Q, to fish, insteas of A, B, C". It doesn't make much sense, and there are a lot of major gaps. It goes against the ability of someone to be self aware. However, Ni is a pattern seeker to sort of make up for this lack of order. This drives a lot of Ni-doms to try and back-track and figure out what the gaps are, very often using Ni again, which finds the gaps, but creates more gaps. As you can imagine, this can lead to a really illogical person left unchecked and undeveloped. Ni doms can convince themselves they are super self aware and see "grand patterns" all the time, because Ni demands the individual do so. Hence, self-awareness is common. However, it does not mean they will do it correctly. This is why you can see a lot of Ni-doms get sucked in conspiracy theories, religion, etc..
I have put a lot of effort into trying to fill "the gaps" for a long time, as it leads people to take me more seriously. With time, I have sort of seen how Ni works, by being brought to seeing the things that Ni brings to my attention that I normally would not pick up on. In essence, Ni works really fast, and pulls things past our conscious processing; it bypasses filters. With time I've been able to see a pattern and reasoning behind this. Ni doesn't work in a vacuum. It actually pulls on information we have learned, or information from the environment and it is related to that. The reason many think it does work in a vacuum, is all of it's work is just simply not seen, and not needed to be aware of.
With practice, Ni can be made to seem more concrete.