Added to the Sass readme

sass/README

@@ -5,12 +5,13 @@ $ gem install sass
 
 We are also using Bourbon with sass. They are a generic set of mixins, and functions that allow for more rapid development of CSS3. Find out more about bourbon here: https://github.com/thoughtbot/bourbon
 
-Then to generate Sass files cd to templates directory and watch the sass files for developement: 
+To use bourbon you need to install it with:
+$ gem install bourbon
 
+Then to generate Sass files cd to templates directory and watch the sass files for developement: 
 $ sass --watch sass:../static/css/ -r ./sass/bourbon/lib/bourbon.rb
 
 To generate a compressed css file for production:
-
 $ sass --watch sass:../static/css/ -r ./sass/bourbon/lib/bourbon.rb --style :compressed
 
 These will automatically generate the CSS files on save.