diff --git a/source/install.html.haml b/source/install.html.haml
index f5b8951..2a79925 100644
--- a/source/install.html.haml
+++ b/source/install.html.haml
@@ -66,7 +66,7 @@ title: Install Sass
         first. You can install Ruby through the apt package manager, rbenv, or rvm.
         %pre
           :preserve
-            sudo su -c "gem install sass"
+            sudo gem install sass --no-user-install
 
     %dl#install-ruby-windows
       %dt Windows