If you want to test the plugin in sandbox mode, take the followint steps.
- Access https://developer.paypal.com with your Paypal Business credentials.
- Access the Accounts section and click on the “Create account” button.
- Create the accounts you need to test the plugin: you are going to need a business account (representing the main vendor account) and at least another one of the personal type to associate to the recipient.
- once the test accounts are created, enter the plugin settings panel and enable the sandbox mode.