How to use the "Text-to-Speech" feature on your kindle keyboard?

1. First make sure the Text-to-Speech is enabled ( you will see sth like " Text-to-Speech: Enabled " on the right side of the image of the book on AMAZON website)  for the book you want to read. If not, you cannot continue. 
2. Press the five-way controller to navigate the book, then press the center of the controller to open it.