How to set up an Airport wifi network
This "recipe" was originally written for A. Veracka, and involves an older model ("saucer") Airport Extreme; but the principles are the same for any Apple Airport network setup.
1. Get Airport Utility 5.6
2. Launch it
3. Plug in the Airport, wait a couple minutes for it to start up
4. Look in your wifi menu for EITHER "New Airport Base Station" named "Airport Extreme..." OR a wifi network called "Apple Network f1e958" and select it.
5. Airport Utility (a different, newer version) may launch. It will then tell you "this airport is too old, use Airport Utility 5.6 instead." Cancel out of that window and quit THAT copy of Airport Utility. Go back to the other one that you opened in step 2.
6. It should now see the new Airport.
Click "Continue." It will ask if you want to switch networks; click "switch".
Then it will probably say "Reading the Airport Extreme configuration" for awhile. Eventually it should say "Airport Utility found an Airport Extreme with default settings."
7. Do NOT update the firmware! Click "Continue."
8. Give it a name. This will NOT be the name of your network; this is just what the saucer itself is called, like if you had 30 of these to work on. Set a password as well, again it will NOT be the same password that you and your family use to connect to the Internet, instead it's the password you will use (probably only once) to configure this saucer.
9. On the next screen, select "I want to create a new wireless network" and click Continue.
10. Make up a name for the wifi network, and leave "WPA Personal" selected; then, put in a password (twice to verify), 8 characters or longer. Click Continue.
11. It will prompt you to plug an ethernet cable into the WAN port.
This is the port with a circle made of dots; there are two ports, make sure you pick the right one! (You'd want to use the OTHER one later if you had a desktop computer that needed to connect via ethernet.) The other end of the ethernet WAN cable should go to your DSL modem.
12. This is the part that might be tricky. If you have Fairpoint/Verizon DSL, and if it requires a login and password, select "I use a DSL or cable modem using PPP over Ethernet" and click Continue. (If you have Comcast cable Internet, select the first option and click Continue, and skip step 13.)
13. Fill in your account username and password, and you can probably put anything in "Service Name." Leave Connection set to "Always On."
14. Power down the DSL or cable modem, then power it back up.
15. Airport Utility should show you a verification screen; click Update and cross your fingers and wait. If it all worked, then after a couple minutes, you should see the newly-created network in your wifi menu, named whatever you called it in step 10. Select it and connect with the password you assigned in step 10 and see if you have Internet!