In order to integrate with Klarna we need access to your API Credentials. These credentials consist of a username and password. Both are necessary to successfully integrate with your Klarna account.
To obtain your username and password:
Login to your Klarna account here.
Click on Settings (at the bottom of the left-hand sidebar).
Click on Klarna API Credentials.
Click on the Generate new Klarna API Credentials button. This will walk you through the process of generating new credentials.
Fill in the Username and Password on the form on the integrations page in Blue Onion.