When selecting to publish the widget during onboarding, select Install via WordPress in the Before publishing the widget window.

Or, if you skipped the script installation step during onboarding:

In your account, go to Script → Install script, scroll down, and select Install beside WordPress.

In the Installing the script using WordPress window, click the Copy ID button and save the script ID for the later step of plugin activation in WordPress.

Select Go to WordPress. You will be redirected to the WordPress site.

Select Download.

The plugin will be downloaded to your default downloads folder.

In the left-hand side menu of your WordPress account, select Plugins and click Upload.

Drop the downloaded plugin into the highlighted area.

Or,

Click the highlighted area, select the downloaded plugin in the opened window, and click Open.

The installation process begins. Upon successful completion of plugin installation, the Claspo item shows in the left-hand side menu.

Select Claspo in the left-hand side menu, paste the script ID copied on step 2 in the Enter Script ID field, and click Connect.

The plugin installs the Claspo script on all pages of your WordPress site.