Log in with the information that Klarna sent to the email address you specified in your agreement here
Click the menu button in the upper left corner (where it says "Hem" (Home)).
Go to "Inställningar" (Settings).
You can generate new API keys by clicking "Generera nya inloggningsuppgifter för API" (Generate New API Keys). Remember to save the API keys somewhere safe, as you can only see them once.
Send us "Username (UID)" and "Password". You can send an email to firstname.lastname@example.org