Updated docs

Author: JanDC

README.md

@@ -6,4 +6,6 @@ This effectively enables you to create critical css.
 The bulk of it's code is based on, and expanded from, Thijs Verkoyen's inline css library.
 
 ### Usage
-This library is used as a twig post processing module in JanDC/critical-css-processor. But you could of course make your own implementation.
+This library is used as a twig post processing module in JanDC/critical-css-processor. But you could of course make your own implementation.
+
+To get a complete instruction in how to use this library (in conjunction with a twig wrapper) please refer to https://github.com/JanDC/page-specific-css-silex for the reference implementation or the critical css processor for a more generic implementation.