My parents were very fundamentalist.
The best advice that I can give you avoid religious discussions whenever possible. If it comes up anyway, then always remain calm, cool, collected and rational. Don't pretend to be possessed by devils or demons, or anything like that. Instead, act bored and treat the debate like it's totally uninteresting. Treat the existence of Hell and YECism as silly superstitions left over from less civilized and uneducated time, unworthy of serious consideration. If someone presses the issue, quickly point out about four or five of the logical inconsistencies or evidences of why it couldn't be true and then say something along the lines of "it's no different than believing the earth is flat. Anyway, if we're going to talk, let's talk about something interesting," and then quickly change the subject. When discussing Hell, always assume the moral high ground and don't give a single inch. And use a lot of phrases like, "Use your head, man! That's why god put it there."
I know that that sounds antagonistic. In some ways it kind of is but I've still found it to be the most effective. The reason being that when people just disagree, it's a "I'm right and your wrong and I'm going to convince you," and so they take the offensive. But when someone considers your beliefs to be absurd, it put's them on the defensive. Once you're on the offensive, you have control of the conversation. And so then you can end it by simply not pushing it any further.