Step #1: Assume What You Believe is False!

One way to do this, if you really want to know, is to assume what you currently believe is false. That is step #1. Step #2 is to demand the sort of evidence that a judge would allow in court. Step #3 is to produce that evidence or give up what you currently believe. No excuses. No double standards.

There are exceptions, like disputes over beauty, or other subjective preferences, but the exceptions cannot be the rule.