From the article:
THE BEST WAYS TO WIN AN ARGUMENT EVERY TIME
Timing: Typically, the first person to reply to the thread has a greater chance of swinging the original person’s (OP) view than someone who joins the debate later on.
Alternative terminology: Use words that are different to those used in the post.
For example, if discussing climate change, describing it as global warming in a reply makes more of an impact than using the same terminology as the OP.
Use calm language: The study suggests using ‘calm’ language to make a point is more effective than swearing or using aggressive terms.
In the paper, examples of ‘calm’ words include those that are softer-sounding such as ‘librarian’ and ‘dull’ than harsh, ‘sharp’ words such as ‘terrorism’ and 'erection.'
Length: Longer replies in general also tend to be seen as more persuasive.
Evidence: Using numbers, statistics and examples to back up opinions make people sound more convincing.
To push this point, commenters should specifically write ‘e.g’, ‘for instance’ or ‘i.e’ before presenting these arguments to strengthen their persuasiveness.
Links: Quotes and quotation marks play little role in trying to convince someone, but linking to examples and outside sources does.
Hedge your bets: Hedges indicate uncertainty, and an example is: ‘It could be the case’.
Although this sounds like it might signal a weaker argument, the researchers said it may make an argument easier to accept by softening its tone.
Check the language in the original post: People can ‘pick their battles’ and decide whether or not it’s worth engaging in an argument by studying the terms used by the OP.
Personal pronouns, such as ‘I’ suggest a person is more open-minded to persuasion, but the use of the words ‘we’ and ‘us’ suggests they are more stubborn.
Stubborn people use more emotive and decisive words including ‘certain’, ‘nothing’ and 'best.'
Know when to give up: Finally, the researchers found that after four or five ‘back and forth’ posts have been made, the chances of swaying someone’s view significantly drops.
I think we could all learn from the list. Especially the last point.