This depends what you are trying to do. If you have your own photo and you’re using it to illustrate a point within the text, I think you’d treat it the same way as a figure or table, as the actual photo is in the body of the document. Then you just need to add a copyright statement
Eg c. S.Houston, 2014 and include it in your list of figures. You may wish to add a Creative Commons licence to it (usually CC-BY) if your work is going to be made public so that other people know what they can do with it. This is good practice – see https://creativecommons.org/ for more info.
If your photo is already public, say on Flickr, and you’re just referring to it rather than actually including it, then you could cite and reference it as if it were any other resource, with yourself as photographer. You can see an example of how to do this in Cite them Right http://www.citethemrightonline.com/media-art/visual-sources/photographs-from-the-internet