1. Fist of all install repositories to /etc/apt/sources.list file similar to this:-

deb http://ppa.launchpad.net/chromium-daily/ppa/ubuntu {your version of Ubuntu} main

Where {your version of Ubuntu} could be hardy, intrepid, jaunty or karmic. There are several ways this can be achieved. Probably the simplest and most meaningful way for most Ubuntu users is to edit the file manually by using the command:-

sudo gedit /etc/apt/sources.list

Alternatively Kubuntu users may use:-

sudo kate /etc/apt/sources.list

2. Then you need to install PPA's public key. Do this by typing the following command into your terminal:-

sudo apt-key adv --keyserver keyserver.ubuntu.com --recv-keys 4E5E17B5

3. Update the system; run the following command on terminal

sudo apt-get update

4. Finally run installation command from terminal

sudo apt-get install chromium-browser

5. That's it! If the installer does not create a menu item for your new browser then you can always launch it from the comand line, thus:-

chromium-browser