When testing an e-commerce solution you often need to create more than one account.
Probably you want to create multiple accounts to impersonate multiple customers.
Google offers a very nice solution where you can use YourAccount+CustomerX@gmail.com
With this you can create as many virtual email addresses as needed. All system will recognize these email addresses as unique address, but all emails will end up in the same gmail inbox.
For more information see;
https://gmail.googleblog.com/2008/03/2-hidden-ways-to-get-more-from-your.html