Your FTP login is your Sitemason username plus your domain, formatted like the below:

user-domain

with a hyphen before the domain, not including anything past the dot (.). For example, if your Sitemason username is 'smuser' with the domain sitemason.com, your FTP username would be:

smuser-sitemason

Your password is the same as your Sitemason.

The FTP server is ftp.sitemason.com or ftp.yourdomain.com