Using Twitter Bootstrap with Rails 3.1 and SASS

application.css

// app/assets/stylesheets/application.css  
/*  
*= require ./bootstrap  
*= require ./sass_main  
*/   

Gemfile

gem "less", "~> 2.0.6"

Shell

user:~/my_app $ git submodule add https://github.com/twitter/bootstrap.git app/assets/stylesheets/bootstrap  
user:~/my_app $ git submodule init   
user:~/my_app $ git submodule update