1. Go to Instagram website and connect with your logins
  2. Go to the Developper page and click on Register Your Application
  3. You will be asked to your website url, your phone number (you can give a fake number) and a short description
  4. Submit and click again on Register Your Application
  5. Enter a name (the name cannot contain the word instagram), a description and your website url again
  6. On the field OAuth redirect_uri, paste the URL above and click on Register
  7. Now copy the Client ID and the Client Secret to Instagram2Piwigo configuration
  8. You're done!