If you want to test PayPal with your shopping cart, you should use the sandbox. To set this up, use the following steps from PayPal.
- Log in at https://developer.paypal.com/.
- Click Test Accounts.
- Select the test account.
- Click Enter Sandbox Test Site.
- Log in and click Profile.
- In the Account Information column, click the API Access link.
- Click the Request API Credentials link.
- Select the API SSL client-side certificate radio button.
- Select the checkbox next to I agree to the API Certificate Terms of Use and terms incorporated therein.
- Click Submit.
- Click Download Certificate. Note the API username and API password; you need them later with the certificate to make an API call.



