The Golden Rule (for us): people do business with people they know, they like, and they trust. - To be known, you need to make an effort to connect and build / maintain a relationship. That doesnt mean you need to be friends but you can't be one and done. Listen to clients and prospects and learn about what they care about and remember it the next time you speak. - To be liked, be genuine, forthcoming, a good listener, etc - To be trusted, always operate with integrity and NEVER sell something you don't believe in. I have a rolodex of clients that buy literally every product we launch before we launch it because they blindly trust us. I will do everything in my power to preserve that trust.
If you only read three books on sales, I would recommend the following. The value of #1 is 1000x all others. Read it and put the principles in practice and you will have laid a great foundation for success in life and it automatically puts the Golden Rule in practice.
1- Dale Carnegies How to Win Friends and Influence People 2- Getting to Yes 3- Influence, the Psychology of Persuasion
The above covers disposition. Process and accountability is a HUGE driver of success in sales. At our company, we DEMAND you have strong systems of accountability and follow through. I find the best salespeople are constantly thinking about their funnel. I was in a lecture in college with Larry Silverstein (NYC real estate billionaire) who said success can be quantified pretty easily: make 10x more phones calls and you'll be 10x more successful. You'll hear this as a recurring theme in life, as Wayne Gretzky said "you miss 100% of the shots you don't take" and woody allen said "90% of success is showing up". Show up every day and put in an honest days work building and maintaining your funnel, and conduct yourself reasonably and with integrity, and things will close.
There is so much more to this topic and it varies from being average to being good to being a top producer... but I think the above is the pre-req.