When I printed off the labels for the URL and Rock Code for the bottom of the rocks, I also printed off labels for pictures. Here you see that I have taped a white paper on the wall and I have a curve to the sheet anchored onto a table. I place the rock on the paper and have a back drop if I need to take a picture strait on or from the top. I place the code on the paper or bend it a bit to make it stand. The sheet with the labels on it helps me to know what rocks I'm missing. I would imagine that you could use a white board, name tents, or have the kids make a sign as well as their rock. This was just the way I did it.
Once you have all the pictures, you need to send them to the RockThought staff. Emailing is fine but with a mass group of images like this project was, a Flickr or Picassa folder was helpful. Click here to see mine.