Here is the best place to start. Not a book on sales. A book on how to craft a message that will be heard by your audience.

https://www.amazon.com/So-What-Communicate-Matters-Audience/...

Short and sweet.

If you want to learn how to do it better, I can't recommend this book enough, "So What?" by Mark Magnacca.

https://www.amazon.com/So-What-Communicate-Matters-Audience/...

Spend the $10 and become a better communicator.