INSTALLATION:

First of all see that the on-site messaging platform is activated from the merchant platform. After it’s done you need to get prepared for the pre-requisites.

One requires either Klarna Checkout for WooCommerce or Klarna Payments for WooCommerce to be installed. If you don’t have click in the above highlight.
You can download the plugin directly via the Klarna Add-Ons menu in WooCommerce or via this download link.

Then same as for all other WordPress Plugin follow the below steps:

Download the zip file and unzip with the respective extractor application.
If you use the WordPress plugin uploader to install this plugin skip to step 4.
Remember the destination of your plugin and upload the entire plugin directory to your /wp-content/plugins/ directory.
Activate the plugin through the ‘Plugins’ menu in WordPress Admin.

CONFIGURATION:

Navigate to the settings for either the Klarna Checkout or Klarna Payments gateway ( WooCommerce –> Settings –> Payments ). At the bottom of these pages you should will see a section called Klarna On-Site Messaging.
Data Client ID – This is the credential you have obtained from your merchant portal. Now copy the value entered inside the data-client-id (just the string inside the double quotes)and paste it in the settings field. See the below image:
Enable the Product placement – Check this box to display On-Site Messaging on product pages.
Product page placement data key – Enter the product page data-key received from your merchant portal.
Product On-Site Messaging placement – Where on product page the Klarna on-site message should be displayed.
Enable the Cart placement – Tick this box to display On-Site Messaging on the cart page.
Cart page placement data key – Enter the cart page placement data-key (retrieved from your merchant portal).
Cart On-Site Messaging placement – Where on cart page the Klarna on-site message should be displayed.
Accept the terms and condition and check the box and press log in.