Getting Started with Your Mac and Mac OS X Tiger: Peachpit Learning Series

When you choose Custom, a little naming dialog pops down from the top of the Address Book window. Just type the new name (in this case, type the word "Cell") and click on the OK button. Now, this new field will be named Cell. Go ahead and type my cell number: "727-555-1214," and then press the Tab key to jump to the Work Email field.