In this tutorial, we learn how to allow only your computer to access your Wi-Fi while using Apple Airport. First, select the Apple Airport Express item on the base station chooser. Double click this and press Configure, then enter your password in the new window that pops up. Now, a new window will open, and you will need to click to "Access Control" tab on the top of the window. Next, click "add" and then select "Mac address" and enter in your MAC address and description. Once finished, click "update" and you will be all set for only your computer being able to access your Wi-Fi!