Navigate to Amazon (www.amazon.com) and click "Sign in." Sign in with your author account if you published the book electronically, or with a generic Amazon account if you published in print.
Find your book's sales page by entering the title, in quotation marks, in the search field at the top of the page. Scroll down to the "Tags" area. Enter a relevant tag in the "Your Tags" box, then click "Add."
Add as many logical keywords as possible by entering the keyword, then hitting the "Add" button. Ask friends, family, and colleagues to enter the same tags. Track your sales and monitor for an increase before adding additional tags.