Don’t get angry, the key of any argument is remaining calm, anger will cloud your judgement, anger will cause you to say words you regret. There is no future in anger except sadness and revenge. Don’t think the words “He wronged me”, “He humiliated me” “He stole from me”. Down that path only lies more anger.
If you feel angry, end the dialogue, walk away, continue it later. Anyone who screams or yells in rage in a dialogue is considered to have lost, both the argument and their dignity.