how can I enable tethering on the iPhone?

Enable tethering on the iPhone by tapping Settings > General > Network > InternetTethering.

Tap Internet Tethering to switch it on.

Connect the iPhone to the computer using USB or Bluetooth.

USB

• Connect the iPhone to the computer using the USB cable.

•  If necessary, follow any prompts on the computer to configure a new network connection.

Bluetooth

• Enable Bluetooth on your iPhone and computer.

• Pair your iPhone with your computer (Windows):

  • Click the Bluetooth icon in the Notification area (system tray), select Add a Bluetooth Device, and follow the onscreen instructions.

  • When pairing is complete, click the Bluetooth icon in the Notification area, selectShow Bluetooth Devices, highlight your iPhone, and then click the Propertiesbutton.

  • Click the Services tab, then check the Wireless iAP checkbox, and click OK.

• Pair your iPhone with your computer (Mac OS):

  • Open Bluetooth Preferences, click Set Up New Device and follow the onscreen instructions.

  • When pairing is complete, make sure the option Use device as a network port is selected.

• Connect to your iPhone (Windows):

  • Click the Bluetooth icon in the Notification are (system tray) and select Join A Personal Area Network.

  • Click Connect.

• Connect to your iPhone (Mac OS):

  • Click the Bluetooth icon in the menu bar, choose your iPhone, and then chooseConnect to network.

Your iPhone should now have a blue bar at the top of the screen to show that Tethering is working.