I just wanted to post an update to the post from the middle of last week. It’s been a few days since I put up my first ad on Amazon. I haven’t had any new sales yet. Boo! but I expect there is a learning curve to it, and on the bright side I haven’t spent any money. Yep not a single penny.
Amazon said that as of right now between two ads 32 people saw my book without my 
spending a penny. Most of them were in the last 24 hours from a new ad I started yesterday. That doesn’t sound wonderful but the more people see my book the more they will consider it for future purchase. It also has a review now (4 stars yeah) so that should help. Another author told me readers have to see your book 4-8 times before they actually purchase it. So here’s to free advertising.
As far as the ad itself manual targeting is the way to go. Amazon makes it super easy once you get into it but they aren’t very good at explaining it. When you set it to manual targeting the give you a list of search terms to pick from that your book appeared under in the past. You can add all of them, some of them or none of them. You can also add your own search terms. In my case I took out a few words and added space opera. I ended up 
with 20 key words. As the metrics come out I will pair that down.
I haven’t had any clicks yet so I launched another ad with different wording. Goodreads recommends you do the same thing. You can always pause or delete an ad that isn’t working. Keep a close eye on your metrics so you know how it is performing. Too many clicks and no sales is a waste of money.
Good luck and I’ll keep you posted.
R. Tran Books 