Here’s a quick snippet to install Ruby on your Ubuntu system. RVM = Awesomeness!

login as single user, not root.

bash -s stable < <(curl -s https://raw.github.com/wayneeseguin/rvm/master/binscripts/rvm-installer )
echo '[[ -s "$HOME/.rvm/scripts/rvm" ]] && . "$HOME/.rvm/scripts/rvm" # Load RVM function' >> ~/.bashrc
source ~/.bashrc

Check out the requirement packages

rvm requirements 

install the packages using sudo apt-get install ..

rvm install 1.9.2

Takes a lot of time

then to start using it

rvm use 1.9.2
[code]
if you want to load ruby as soon as you login 
echo 'rvm use 1.9.2 # Load Ruby' >> ~/.bashrc