Discourse app folder on digitalocean or any server

I am very new to Discourse, i had just installed via digitalocean one click app installer for live site http://www.frontpageofindia.com/.

I need to customize the header section but i m not able to find the app folder on server.
It has /var/discourse/ have only .yaml files.

Search here for “theme #howto”.

You should also search for “install cloud” to learn about the recommended way to install Discourse.