diff --git a/README.md b/README.md
index e11794b..109873d 100644
--- a/README.md
+++ b/README.md
@@ -41,7 +41,12 @@ Or install it yourself as:
 
 ## Usage
 
-TODO: Write usage instructions here. Describe your available layouts, includes, sass and/or assets.
+Add or update your available layouts, includes, sass and/or assets.
+
+GitHub Pages runs in `safe` mode and only allows [a set of whitelisted plugins](https://pages.github.com/versions/).
+To use the third-party gem in GitHub Pages without limitation:
+
+* Here is a GitHub Action named [jekyll-deploy-action](https://github.com/jeffreytse/jekyll-deploy-action) for Jekyll site deployment conveniently. 👍
 
 ## Development