First, get this FTP program (there are numberous more but this one is best to my opinion):
SmartFTP
When you have downloaded it, install it and configure it a bit (Basically, all you need is your cPanel login username and password, and a port to connect to (i cant remember what it is) will post the port later if needed.
Then, it is all very easy, you can download and upload files from and to the server (your hosted space) and with NotePad (simple but effective, no downloads needed aswell) you can edit anything.
If you're using SmartFTP, when you are in your webspace (within the application) just drag the file you wanna edit to your folder (on your hard drive), when thats done, open that file with an editor (Notepad) and edit wherever necessary), then save it and drag it back to your hosted webspace, it will ask you if want to overwrite the existing file, well you edited so yea overwrite ^^
thats it!
Hope it helps
