What everyone else said, plus this: where possible have witnesses to important conversations. Until my children were old enough to hear/participate in family conversations, I would think I was communicating with my N, only to find out that he had ignored or worse, changed what I said. I sometimes doubted myself, as he would argue very convincingly that I had not said what I believed I had said to him.
When the children got older, they would confirm that I had indeed said something and he had apparently agreed to it. This was the only thing that seemed to shake him (temporarily) out of the certainty of his rightness. Having said this, I don't recommend involving children as it forces them to take sides. I suppose if a narc will agree to joint counselling, this is a good venue to have important conversations as you have a witness in the counsellor.
During our divorce, after every conversation I immediately sent a courteous, business-like email confirming what had been said or agreed. I kept copies of these. It closed the door on opportunities for him to come back later and tell me I had agreed to something entirely different.
Yelling got his attention, but I hated the person I was becoming.