To access your site by FTP, use ftp.yourdomain.com as the FTP hostname. The user details you need to enter are e-mailed to you at signup, and can be viewed in the My Services section of the member centre.
If you have set up custom FTP users in cPanel, the FTP username will be in the form of user@yourdomain.com.
Please note that for security reasons, we highly recommend you enable the SSL option in your FTP client, which will encrypt your password and data. Our servers fully support secure FTP (SSL/TLS) along with SFTP.