The following guide is applicable to all wireless devices other than Keyfobs, the Keyfob how-to is here

Step 1 of 6 : Enter System Programming

This step is easy enough, all you need is the Installer Code. Assuming you're programming a new system, the factory Installer Code is 5555. The command to enter programming is * 8 (the asterisk button then 8)

Press * 8 then 5555

If the proper Installer Code has been entered the keypad will chirp five times and the red armed light will be on to indicate the system is waiting for a three digit program section to be entered.