When I signed up with Kindle, I did join KDP Select, which gives 5 days (per 90 day period) where you can promote the book for free. I learned that for non-fiction mid-week is the best time to run the free promotion.
So I decided to run a two-day test of free promotion. I setup the promo to start the first minute on Tues. and run through the last minute on Wed. During that time, I posted on my FB page, sent an email update to my list, and posted to 2 LinkedIn groups. I also asked my friends to share the update on FB.
During those two days, it was lots of fun to watch the stats. By the end of the day on Wed, the book had moved all the way up to #1 for the main category I had chosen, which was Small Business & Entrepreneurship > Entrepreneurship.
It was the free promo, so there was no immediate revenue associated with that #1 ranking. I'm not sure yet if there is a right way to market that #1 (I took screenshots of Amazon), or if it is worth doing marketing with that at all, as again that is on the free side.
However, here is where it gets fun. During those two days, the book was downloaded over 650 times. And in the book is my intro/bio and links back to my various sites/pages. Now I have my own Kindle, and I know 100% for sure that lots of people download the free books and never get to them, so even though there was over 650 downloads, I know that no where near that will read it.
In the future, I'll be much more strategic with my intro/bio and also with my included links. I have lots to learn, this has just been the first test, but there sure is an incredible amount of opportunity with Amazon - far more so than the direct revenue opportunities of selling books.
I'm no expert on Kindle by any stretch, but if you have any questions, please let me know!