I have recently came across the book called How to Have a Impossible Conversation while I was searching for some practical advice for how to argue better. The book was so good, I thought everyone has to know it.
Arguing with someone and try to understand and persuade her has always been an interesting field of interest for me. You start negotiating once you wake up in the morning till the minute you put your head on the pillow. Even if you are not negotiating with someone, you battle with your inner self all of the time.