feature: optmize wallet-connect sign README

basic/78-wallet-connect/v2/sign-example/README.md

@@ -1,3 +1,29 @@
+# Wallet Connect Sign Demo
 
-# Reference
-- https://github.com/WalletConnect/web3modal-examples/blob/main/walletconnect-modal-sign-react/src/pages/index.jsx
+This demo showcases how to set up Wallet Connect with React, using `wagmi` and `web3modal` for blockchain connection and user authentication.
+
+## Setup Instructions
+
+1. **Install Dependencies**
+   ```bash
+   yarn
+   ```
+
+2. **Create `.env` File**
+
+   Create a `.env` file in the root of your project and add your Wallet Connect Project ID. You can obtain a Project ID by signing up at [Wallet Connect Cloud](https://cloud.walletconnect.com).
+
+   ```plaintext
+   REACT_APP_PROJECT_ID=your_project_id_here
+   ```
+
+3. **Start the Demo**
+   ```bash
+   yarn start
+   ```
+
+## References
+
+For more details, see the following resources:
+- [Wagmi Getting Started](https://wagmi.sh/react/getting-started)
+- [Wagmi Connect Wallet Example](https://wagmi.sh/examples/connect-wallet)