There are two methods of managing the files on your web site. You can do it via the control panel, or via FTP. Most people use FTP. Here is a brief description of how to use each method.
Log in to your control panel. From here, click on My Services then click the Green Square Icon to the right of the domain you want to edit. Then click the Logon to Plesk button.
Once in the Plesk control panel, click the Home icon, then click the domain name that you want to edit. There you will see an icon called File Manager. With the file manager you can manage your files.
Most web editing programs like Adobe Dreamweaver has FTP built in. There are also many free FTP programs that you can download. Whatever FTP program you choose, the configuration will be very much the same. Here is the information you need to configure your FTP program
Host Name: ftp.YOURDOMAIN.COM (replace YOURDOMAIN.COM with your domain)
Start Directory: httpdocs (all lower case)
You will also need to know your username and password. You can locate your username and password by logging into the control panel.
How to Find Your Username & Password
From here, click on My Services then click the green square icon next to the domain you want to edit.
Within this setup area, you will see your FTP Login which is also known as your FTP username. You can not view your password but you may enter a new password here. If you change it, be sure to write it down so you have it for next time.