how to argue your point (in philosophy)

1. Discussion is a civilized enterprise between two (or more). One talks one listens.
2. Be always prepared.
3. DO NOT talk on top of your interlocutor. Wait until they finish their point. expect the same, if they interrupt you politely say: "Excuse me, I'm not finished."
4. DO NOT EVER raise your voice (it shows you're emotionally invested making your argument weak).
5. DO NOT hurry, avoid speaking fast. you need to be in command of your thoughts. take your time to answer back; be deliberate and in control.
6. If there's room for agreement, say: "I agree," or "That's a good point." it makes your interlocutor feel comfortable, which is always good for you.  
7. Be generous (even if you're winning). how? give a point if you can, for ex. "You're right about that."
8. Be affable throughout the exchange. smile if there's a chance (there always is). affability shows you're ease which shows open mindedness, a great trait of character.
9. The discussion doesn't have to be won. not in one meeting. you can say "we should continue this at some other time."