When you are ready to begin testing, you will need to create Visa Checkout consumer test accounts in the sandbox and add at least one payment method to them. You can start by creating your own test consumers when the Visa Checkout lightbox is opened. You will be shown an Add a New Payment Method screen in which you must enter a card number.
We would strongly recommend implementing this extension on a development environment before putting it live.
Note: You can enter any values on this screen which make sense to you, except that you must use one of the following card numbers. The name on the card, expiration date and security code are not validated in the sandbox, so you can enter any valid value. Because card numbers are validated by Visa Checkout on entry, you should only use these numbers for sandbox testing.
Card number 4242424242424242
Card number 5500005555555559
Card number 340353278080900
Card number 6011003179988686