diff --git a/README.md b/README.md
index ccd2f0e..4302e41 100644
--- a/README.md
+++ b/README.md
@@ -18,6 +18,13 @@ Or install it yourself as:
 
     $ gem install jekyll-gist
 
+Finally, add the following to your site's `_config.yml`:
+
+```
+gems:
+  - jekyll-gist
+```
+
 ## Usage
 
 Use the tag as follows in your Jekyll pages, posts and collections: