try their new spicy chicken biscuit before they put it on their menu! All you have to do is go here to pick which restaurant is closest to you, and then you pick the time and date that you want to reserve. The dates are January 3-8 during breakfast hours. You will receive an email with the information that you need and you print it out. Easy as that! I got to do this when they were introducing the spicy chicken sandwich too.
Keep in mind, not all restaurants participate. And many times and certain dates may not be available. There are a limited number of reservations for each Chik-fil-a, so reserve ASAP!