Create new Amazon application
To start using amazon login, you must create amazon application. View this tutorial and do follow these steps.
Note: You must containt a Amazon Developer Center account. If you don't, create new one by this link http://login.amazon.com/
Step 1: Go to https://sellercentral.amazon.com/gp/homepage.html
Step 2: Click Register new application.
Step 3: Fill up your app settings, click Save.
Step 4: When creating success, click Web settings to get client id and client secret.
Write down 2 values and move to amazon login