diff --git a/README.md b/README.md
index 98c7ea7..977a915 100644
--- a/README.md
+++ b/README.md
@@ -9,6 +9,7 @@
 git clone https://github.com/MSakamaki/mock-lib.git
 cd mock-lib
 npm install
+npm run build
 npm start
 ```