It depends on how big the file is; please look at these two methods for further information:
FTP - File Transfer Protocol is a good way to upload multiple files efficiently and effectively, with a simple-to-use drag-and-drop system, FTP is good for larger or multiple files. Examples of an FTP clients are FileZilla and Cyberduck.
cPanel File Manager - This online file manager is a good way to upload files from anywhere on-the-go, with an easy to use interface and fairly good upload speeds. cPanel File Manager is good for uploading single/smaller files.
For more information please look on our wiki:
http://x10hosting.com/wiki/How_to_Upload_Files_to_Your_Website