Go to this link: https://www.amazon.com/gp/help/customer/display.html?nodeId=200486880 and then follow the instructions so that your readers can get a sample of your book or look inside it before they purchase it.
To actually sign up for the look inside go here: https://www.amazon.com/gp/html-forms-controller/SITB_Pub_Signup_Form. Make sure you read everything on the page and at the bottom of the page you have to fill out your information then click on submit.
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