I'd figure maybe a few blog readers would be wondering the same thing.
The answer is a mix of a lot of methods. It does get tricky trying to remember where all the cameras are at all times since they get moved a lot.
The first thing I always do is write it down with a pen or pencil. Trail names, trail features, and landmarks are important here. I also look at my GPS and write down the coordinates.
I also have an app. on my Android called "GPS Share" that allows me to access the phone's GPS, extract a coordinate, and text message it to anyone. For a few places I camera-trap at, I send these via email to managers and people who need to know where my cameras are. A backup email is also sent to my email address.
The GPS Share app. is a free one that works well. It's quick, easy, and is basically all I need for what I'm doing.
Another method used to keep track of the cameras is logging and flagging a waypoint on my phone's GPS. Basically, what this means is that I am able to save each camera's location on my GPS map. I get a phone ringtone when I walk within 20 yards of the camera-trap and a different ringtone noise when I walk within 10 yards of the camera-trap. This way, if I really forget where a camera is, I can always pull out my phone and have a good idea of the range that it is in.
Do you use any of these methods in the woods with camera-traps? Are there any better Android apps that I should use instead?