From the main interface, click on SMTP Servers button
Now at the left side, click on Add SMTP User button
To add SMTP user, we support all the popular email providers, such as: Google, Hotmail, Outlook, AOL etc. If you want to add any of of those, then just select from the list, provide email and password. You may also need to check Secure connection Use (SSL) option
Just in case, if your provider is not on the list, then choose Not in the above list and select SMTP Server
Then you may need to provide, email, password, SMTP host and SMTP Port (Usually 465) and select Secure connection Use (SSL) click on Save