Sass is a default for CSS development in Rails so I recommend installing Thomas McDonald’s bootstrap-sass gem.
bootstrap-sass in the Gemfile
$ bundle install
//= require jquery
adding a new file app/assets/stylesheets/bootstrap_and_overrides.css.scss file
Twitter Bootstrap provides additional elements for a more complex page layout.
Replace the contents of the file app/views/layouts/application.html.erb with this:
ERB version: https://gist.github.com/xuncheng/5998747
HAML version: https://gist.github.com/xuncheng/5998755
For CSS styling with twitter bootstrap, create a partial for flash messages in app/views/layouts/_messages.html.erb like this:
ERB version: https://gist.github.com/xuncheng/5998767
HAML version: https://gist.github.com/xuncheng/5998779