My book will help [audience] to [benefit] by [method].
Some examples:
My book will help female executives to become more successful by mastering the use of sports metaphors. [Audience and method defined, benefit left vague.]
My book will help readers to respond more spontaneously during job interviews by applying Second City improv techniques. [Audience left vague, benefit and method defined.]
My book will help managers under 30 to feel confident when supervising older subordinates. [Audience and benefit defined, method left undefined.]
Another example is to select parts of your index based on geography, events, or dates to appeal to local media. And know your audience: My Bad