I have a great tip and rules for arguing :
Rule 1 : take your opinion as right until opposition.
Rule 2 : if opposition, ask the other why your opinion may be wrong, or even confront his opinion with yours (better if you have a "complete" opinion) .
Rule 3 : check if his argument makes sense and explains flaws in your opinion. They don't have to be always right, but there may are some fact that you missed
Rule 4 : if necessary, add or replace some part of your opinion with what the other said. Do NOT completely override yours, unless you know literally nothing.
Rule 5 : repeat to get a more complete opinion.