You can also upload your files through your control-panel.

1. Login to your hosting control panel:
   http://www.helpinghost.com/h-cp/
2. Click on the Webshell3 Icon
   
   

To learn how to use Webshell, please take a look at this tutorial and the help inside webshell:
Click here for a Video

IMPORTANT!
You need to upload your files into the directory /yourdomainname.com !