Nvictor you are seriously trying which is more than most people are doing.
A few probing question I would have if I was reading your book would be as follows:
1. How does a salesman think. What are his thought processes when meeting and dealing with people.
2. Does he position himself physical in any particular position (i.e. up close far away)
3. Does the salesman deliberately talk in a different tone.
You must realise that when you look at another person they are thinking. Having thoughts - we all do. When you look at someone, he/she could have a happy smile on their face but their mind is thinking thoughts that are maybe, judging you, classifying you, making fun of you, thoughts that you hope you will never know. So understanding that you have a good place to start from. WE ALL HAVE THOUGHTS, same beautiful and others terrifyingly horrible.
A salesman THINKS, looks at people differently. They have a PURPOSE. This purpose thing the Paul mentions in his PWMS applies across the board. In every facet of our lives. Those people that continually have a purpose are the ones that succeed in life. They're the ones you see that have drive, ambition etc. Purpose encourages focus, drive, energy to grow etc.
A salesman has a purpose, so you must too. When you meet people realize they think as well. Define your purpose when you meet a person. For example, give them the impression I'm happy to be alive. But to give that impression you must all ready know what you must say to come across as being happy. Then go to the library with the purpose of finding a book the helps me to come across as a happy individual who really enjoys life through talking. You keep doing this all through your life. Identify what it is you want to change, have, need etc. Then state your purpose. It is a never ending cycle until we die. But realise your OTC never stops processing.
You also mentioned that you would like to be a good persuader, live a better life, be more confident, and be a good talker. I can see four purposes for reading the book in that statement.
Purpose 1: Develop the mindset to be a better persuader.
Purpose 2: Understand and implement into my life strategies to help me become more confident
Purpose 3: To extract all ideas that will help me to live a better life
Purpose 4: Locate any and all ideas that will help me to understand what makes a person a great converstionalist.