To use FTP you need a FTP client (Filezilla works but you must disable the option for multiple connections otherwise the firewall may block you.)
settings --> Transfer --> Concurent transfers - set all three to "1"
CAUTION: Your IP can be blocked with x10hosting's firewall - by too many "Failed" FTP logins in a short period
The FTP details you need for FileZilla or other FTP client:
Host: (your account's primary (main) domain) or (your server's IP) - Port: 21
Protocl: FTP - File Transfer Protocol
Encryption: Use plain FTP
Logon Type: Normal
User: (your cPanel user name)
Password: (your cPanel password)