Ask me the most important book any young flight instructor can purchase to succeed in business, and I wouldn't hesitate to recommend Dale Carnegie's How to Win Friends and Influence People.
I discovered this book in high school, when a very smart man (my daddy) gave it to me and said, "Read it and you'll know what it takes most people a lifetime to learn." He was right.
Almost anyone seeking a flying job can fly an airplane. What's not true is that everyone who wants to be a pilot can get along with others, much less make others like them. That's where Dale Carnegie comes in. For instance, one of Carnegie's rules is, "Always speak in terms of the other person's interests." Imagine that. If you want to influence someone and make a friend, then you should find out what is interesting to him, rather than trying to get him interested in you. The latter will eventually follow from the former.
Carnegie says that the deepest principle in human nature is the craving to be appreciated. Yet most folks completely disregard this principle and instead attempt to get others to appreciate them. Is it any wonder some people just don't connect with people?
Few people are ever introduced to Carnegie's wonderful book. So, I'm making the introduction. Keep your TERPS, AIM, and FARs handy. Study them intently. But read How to Win Friends and Influence People to learn the best-kept secrets of getting along with others, and helping them to like you.