Install FireFTP. Go to the first resource (while running Firefox) and click the "Download FireFTP" link. Click "Allow" and "Install Now" when prompted. When the installation finishes, click the "Restart Firefox" button.
Click "Tools" and "FireFTP."
Click "Quick Connect." Under "Host," type in the name of an FTP server. If you are unsure of one, you can use the FTP server for the University of Idaho: mirror.its.uidaho.edu. Select the "Anonymous" box, since you do not have a user account for this server. Alternatively, if you have a username and password, enter them in the appropriate login boxes.
Click "Connect." Your computer's file system will be displayed on the left, and the file system for the server will be displayed on the right. To upload a file, select a file on the left and click the "->" button. This may fail if you lack write permission to the server. Generally, only users with passwords are able to write to a given FTP server. To download, select a file on the right side and click the "<-" button. It will begin transferring to your computer. The log on the bottom of the screen will give you an estimate of how much time remains for the uploads or downloads you have going.