Hello Chris.
Welcome to Airport-Data.
You will find an explanation of how to create folders under the "Help" section of your Member Section.
However before you jump in, you need to give some thought as to how you wish to arrange your photos.
I my case, I created folders for each aircraft type, i.e. Airliners, Helicopters, etc.
Then sub folders for manufacturers and the below each of these the aircraft model types. I find that this enables me to find particular photos quite easily.
Others file by the airport where the photos were taken, by the event at which photos were taken, and so on. Click on to a few of the "Top Photographers" on the front page to view some alternatives.
Having first created the folders, go to Aircraft Photos in your Members Section, click on the little down arrow at the end of the field on the RHS of each image, and the list of folders and sub folders you have created will appear. Click on the chosen folder.
Malcolm.
Admin.