Get out and sell.
Get in front of as many people as you possibly can as fast as you can.
Learn your own style. Build a strong value proposition. Discover what your market wants. Create a "funnel".
If you insist on reading - make sure that the method | process | system matches your values.
A great place to start is to study copywriting.
If you are interested in recommendations for where to find best-in-class materials to learn from give me a call.
Good luck!