Do you have a developed WordPress site and corresponding database ready to go?
If yes, use some FTP program and upload your files. You'll FTP to example.com (your domain name) and see an example.com folder there. Go into that folder and upload all of your content. If you have a database dump, go back to that first directory you saw and upload your database file there.
If no, use the One-Click Custom (formerly "Advanced") Mode installation. Yes, this is the really easy to install WordPress here.