The best way to upload your web site is via FTP. This can be done in a number of different ways using many different FTP clients. Every client needs 4 things:

1. Domain name or IP Address.
2. Username.
3. Password.
4. Port (Usually port 21)

The files for your site main site will need to be uploaded to the public_html folder. To see how to publish your site to an Addon Domain please see: FTP for Addon Domains

Note:The Main Domain and Username can be found in the Stats section, on the left hand side, of your cPanel. The Password is the same as your cPanel password.