I put a file folder on my desktop and name it by the date. So today's will be named March 24, 2015. Then I put today's photos in the file folder. Later I drag it into my Mystery Shopping folder. I have never mixed up photos. As sojo said I also separate photos taken on the same day by a photo of my dashboard in my car. So I might have 13 photos from a gas station, then a photo of my dashboard then the next set of photos. That way I know which photos belong to which location.