how to have a unique side image for each page

I currently am building a wordpress site and would like to dynamically display an image based on the page title. This is my current set up. The home page is set up as the home template. All other pages are set up as the secondary template. What I would like to do is for each secondary page have a side image that is unique to that page. How can I do this? I was looking into custom fields, but not sure if that is that way to go. Any help is much appreciated.

thanks!