File synchronization between stations

I have a session that I started on my laptop. I copied this session over to my desktop. From there I started editing some files, creating TIFF files, making further adjustments to files, renaming, etc. I went back to the original session on my laptop and shot more images, adding to the session. What is the best way to merge the sessions, ensuring all files stay in tact with all the newest versions, tiff files and adjustments?