When it comes to CF cards, it always baffles me when I see my assistants not labeling their cards. These are usually the newbies who work for me and they learn very quickly to change their ways. Every single CF card should be labeled with your name, web address, phone number, and the word REWARD on it. Each card should also be labeled with a number and the year you purchased it. I have a set of 8 gig cards labeled 1-4, a set of 4 gig cards labeled 1-4, and a set of 2 gig cards labeled 1-8. Your cards should be stored and used in their order going forward for one event and backward for another (or however you want to set this up to make sure the cards get used evenly.) It is important to keep them in order so you can keep track of your images once the downloading begins. Even though I back up everything on two hard drives at the wedding or event, I still tend to download them straight from the cards when I get to my office. I start with card one and work my way through auditing the image count as I go to ensure that I have everything. If all your cards are numbered, then you will be sure to have all your ducks in a row. There are other obvious reasons for labeling your cards, but I am sure you get it.
Here is how mine are labeled:
CARD #1 2009