Because while spending four hours trying to get this working, I googled, and heard the screaming of other souls like mine.
1. Open Airport Utility. Click the icon that shows your base station. Go to the BASE STATION menu. Choose “Add WPS Printer.” Click the FIRST ATTEMPT radio button and CONTINUE.
2. On the back of the printer are two little buttons you can only push with something pointy. Push the lower one for LESS THAN TWO SECONDS.
3. Wait a minute.
You’re welcome. Buy my books.