1. On the iPhone 3G/3GS, go to ‘Settings > General > Network > Internet Tethering’ and switch it to ‘On’. When prompted, choose the ‘USB’ option.
2. Windows will recognize the USB connection and should start working immediately. If not, go to the ‘Windows Control Panel’ and open ‘Network Connections’. The iPhone 3G/3GS device will be listed there.
3. ‘Right click’ on the new “Local Area Connection” listed and select “Enable”.
4. Go to a website on your Windows computer.