Step 1: Click on this page https://disqus.com/profile/login/?next=/api/applications/ and log in with your Disqus account.
Step 2: Click on "registering an application" link.
Step 3: Fill in the Register Application fields > Click "Register my application" button
Step 4: On the next screen, enter your domain and Callback URL > Click "Save changes"
Step 5: Navigate to Details tab > Copy the API Key and API Secret to Social Login Pro app configuration page.