Receive and Broadcast Internet From The Same Computer

If you have a Mac outfitted with 2 wireless cards you can use that instead of an Airport Express to extend your wireless connection to your other nearby devices. Here’s How:

1. Open System Preferences
2. Click on the “Internet” tab
3. Select the source of your internet connection in the “Share your connection from” pull-down menu
4. Check the device you’d like to broadcast your signal from in the “To computers using” list
5. (optional): Choose a name and security options for this ad-hoc network
6. Click “Start”

Once running you will see your airport icon change to an arrow to indicate that you are broadcasting your connection:

This post was updated on August 10 to correct mistakes in the original post. Old instructions and images have been removed for clarity.