Template Override for addon


I want to modify the template for the live chat addon. I know I can directly edit the template, but I'd like to know how to create an override. After reading the documentation, I can't figure it out.

The file I want to modify is /skins/basic/customer/addons/live_help/blocks/livehelp.tpl

I already have a my_changes folder created for the styles.css override, but have no idea how to create a template override.

Is this possible? Or do I need to edit the original template file?