Installing Webmin on Ubuntu 14.04

Update Sources List:

sudo nano /etc/apt/sources.list

Add the following lines to the bottom of the file:

deb http://download.webmin.com/download/repository sarge contrib
deb http://webmin.mirror.somersettechsolutions.co.uk/repository sarge contrib

Add Webmin's GPG key to trust their repository:

wget -q http://www.webmin.com/jcameron-key.asc -O- | sudo apt-key add -

Update Package Lists:

sudo apt-get update

Install Webmin with apt-get:

sudo apt-get install webmin -y

Login to Webmin:

https://server_IP:10000

Enjoy!