Book sales by book promotion has to be your highest priority as an author. Writing the book is futile if no one is reading it. Therefore, you need to promote, promote and then promote some more.
Learn different ways you can promote your book. Customized Gmail signatures is an easy and cost-free way of getting your book displayed to every person with whom you communicate.
This is not a boasting process, nor a horn tooting one. As a writer you must promote your book, not hide it with unjustified humility. Sell, sell, sell.
Examine all the information New York Bestselling author, Alka Joshi puts into her automatic signature. Imagine, this signature is added automatically to every email communication she writes: