diff --git a/CONTRIBUTING.md b/CONTRIBUTING.md
index 968e011..508a885 100644
--- a/CONTRIBUTING.md
+++ b/CONTRIBUTING.md
@@ -68,7 +68,17 @@ Go to your fork on GitHub and click "Compare & pull request".
    ```
    You can get your Public API key from the [JigsawStack Dashboard](https://jigsawstack.com).
 
-3. **Start the development server:**
+3. **Build the project:**
+   ```bash
+   npm run build
+   ```
+   or
+   ```bash
+   yarn build
+   ```
+   This creates the `dist/` directory with the compiled library files that the demo HTML requires.
+
+4. **Start the development server:**
    ```bash
    npm run dev
    ```
@@ -77,7 +87,7 @@ Go to your fork on GitHub and click "Compare & pull request".
    yarn dev
    ```
 
-3. **Open your browser and visit:**
+5. **Open your browser and visit:**
    ```
    http://localhost:5173
    ```