If you disagree with an argument, know precisely why you disagree with the argument. Usually it is in the reasoning. Point out flaws.

These days, opinions, misinformation, rhetoric and ideologies make things interestingly irritating, for sure, but they don’t change the way we come by Truth.  We cannot let lies, ideologies, and persuasive rhetoric overrun the basis of civilized societies.  Some may think that the basis of Truth is technology, but the technology and progress that we have achieved, and the achievements are amazing, have only been possible because people in the past have taken the time to fight and protect Truth and the method by which we come by it.  History will attest to this.  Disagreement is an open door to argument.

There is ample opportunity for disagreement and so there is ample opportunity to learn.  An argument often starts with a claim and then is followed by a response and so on.  This is the first thing that needs to change.  How?  Ask questions.

So, you disagree with someone and you have clarified and know what they are arguing.  First, ask for all of their reasons, and then concentrate on one reason at a time.  There are three things to concentrate on: the quality of the reason itself, if the reason supports the argument, and how well the reason relates to the argument.

Afterwards, take note of any flaws and and point them out.  There are many ways of doing this, but a particular favorite method of mine is to simply follow the implications of a particular flaw to its reasonable conclusion, which if it is wrong will contradict the argument’s given conclusion.