diff --git a/README.md b/README.md
index d643491..e394ebc 100644
--- a/README.md
+++ b/README.md
@@ -252,6 +252,7 @@ However, if you used a `bazel-version` input before, you will need to remove it
 To build action, run the following command:
 
 ```sh
+$ npm install
 $ npm run build
 ```