How to test ubercart Paypal-sandbox environment method in a Drupal site - a tester's view ?

Suppose your Drupal projects handles products which can be purchased through online. And you are using Ubercart PayPal and Ubercart Payment modules to handle payments related to purchase. Either registerd or non registered user can buy the product. User can use paypal through two ways. "Can purchase through sandbox environment or Can purchase using credit card". So a tester can test the paypal functionality using both these ways. Here I am going to explain how can you test the purchasing functionality through Sandbox.

Please check the below steps which explains step to step process to test the paypal functionality.

1. Open the site.
2. Add a product to cart.
3. Select transaction through paypal in the checkout page.
4. This will open https://www.sandbox.paypal.com/.
5. Click Pay with my PayPal account. Please refer the below image.
   //login.jpg
6. Then log in the sandbox server using buyer account. This will be provided by the developer. Please refer the below image.
   //login2.jpg
7. Click Continue. Please refer the below image.
   //login3.jpg
8. This will again redirect to checkout page. Fill the details and again click continue checkout.
9. Click on “Submit Order” button for completing the transaction.
10. You will then see a page saying your transaction is complete and order number.
11. You can click History in the sandbox server to see the orders. And can ensure that you order is completed.
    //history.jpg

Hope you understand PayPal testing. Please note that here I specified only one method. Payment using credit card information is not specified here. And the steps may vary depending on the project.