Whoever thought that persuasion is not work but only manipulation then I urge them to close this book right now, from the first pages, and look for a course on manipulation. You will see throughout this book what persuasion is and more importantly what persuasion is not.
Persuasion is dedication. You won't be able to convince the person in front of you that you're his friend unless he sees that you care about him and are committed and willing to look out for his best interests. Of course, this is to your advantage too. If a salesperson doesn't try to manipulate potential customers into buying all sorts of products they don't need but puts himself in the position of a consultant then he will be able to offer the best advice to that potential customer and close the deal that benefits them, that's how win-win is easily achieved. The customer leaves satisfied because he was well advised and chose the best option he could find, and the seller is satisfied because he has made another sale and gained another customer who is likely to remain loyal.
Your strength is your inner ability to leave your comfort zone and look for ways to improve your life by accepting hard work and dedication and turning them into personal investments.
Persuasion can be interpreted as your power to make others see value, the value you place on certain things. You can create value if you have a definite personal value. Basically, you will make a transfer of value that others are aware of to a lesser or greater extent but which becomes an option. Your ability to turn that option into an investment in that person's future ensures your success in convincing them.