The boundaries that affected him, I told him:
I told him I would not have sex with him if he had been drinking.
I told him I was no longer willing to live with an active alcoholic and I would leave him.
Things like that.
Other boundaries were my own, and I would tell him what affected him without explaining that "see I have this boundary that I've set up for myself" -- examples:
I had a boundary that I would not drink with him and his friends. I didn't state that as a boundary, but I said, "since I don't enjoy hanging out with you and Pete and Natasha and drinking and watching sports, I am going to take the kids with me and go swimming on Monday night instead."
I don't know that there's a "right" or a "wrong" way to do these things -- I always saw boundaries as being for me and not for him, so the analogy with government doesn't really work for me. It would if I set up boundaries for him, but I never saw that as my place.