Create your secondary FTP account via your control panel and then use these settings to login:
FTP Server: Yourdomain.com OR YOURIP.
FTP Login: firstname.lastname@example.org.
FTP Pass: secondarypassword.
A secondary FTP account has access to only one subfolder of your public_ftp folder. For example:
Secondary FTP Account: email@example.com
Secondary FTP Root Folder: /home/yourusername/ public_ftp/bob/
If you would like to setup an FTP account for a subdomain, you need to use the same name for the subdomain and the FTP account: