The best way to promote your book is to give away free copies. The next best is to reduce the selling price to less than a US dollar or GB pound. But only for a limited period as every author deserves some monetary reward for the effort they have put into its creation.
I have published two short story collections and two motorcycle travel books for less than one GB pound, but these have been written to showcase my writing rather than to generate much income, therefore their price is set deliberately low. Peatmore Press has published four short audio books through acx.com but here the price is set by acx and Peatmore Press has no control over this even though it would like to set this to less than 1 GBP to bring it in line with its other showcase works.
Most of my free promotions are given away online, as ebooks since these formats entail no cost to the publisher. It is these that generate the most take ups by readers as hundreds are downloaded at a time. Some copies may be given free to selected reviewers, but the majority of the copies that are given free during a promotion period do not generate reviews.
I buy most of the books I read and review each one as I feel this provides the author with valuable feedback whether I like the book or not. I find it sad that those who get hold of any free book from an author do not find time to follow my example. It is even sadder when these books end up on pirate websites and sold for profit.
Peatmore Press Books