docs: Add missing npm install command

README.md

@@ -223,7 +223,7 @@ To start:
 2. Change directory to `/examples`
 3. Execute `docker compose up`. A CAS server for demo purposes will launch at https://localhost:8443/cas
 4. Change directory to `/app-router` or `/pages-router` depending on the router you would like to view the example for
-5. Execute `npm run dev`. The Next.js example app will be available at http://localhost:3000
+5. Execute `npm install` then `npm run dev`. The Next.js example app will be available at http://localhost:3000
 
 **Note:** You may encounter a `NET:ERR_CERT_INVALID` error in your browser when attempting to visit the CAS login page. Bypass the error by trusting the page. The browser is attempting to protect you from visiting a suspicious secure site at https://localhost.