Fixed docs

README.md

@@ -106,6 +106,12 @@ class Post < ActiveRecord::Base
 end
 ```
 
+#### 2. Specify the serializer when you render the object:
+
+```ruby
+render :json => @post, :serializer => FancyPostSerializer
+```
+
 ## Arrays
 
 In your controllers, when you use `render :json` for an array of objects, AMS will