Help with image positions regardless of resolution

I am trying to create a 2D top-down board game, but have the individual board game tiles be placed dynamically so that they can be changed from game to game. I can figure out the coordinates to place a specific image for a specific resolution, but when it changes, so do the coordinates of course. And the numbers I see do not correlate to the board games image at all. I'm sure there is a simple way to figure this out, but it's not coming to me. I'm not even sure how to ask the question, which is probably why I am unsure of what to even search on for answers. Here is a link to a blank board game that I am trying to use as the "skeleton", and would then place different board tiles in each square.

link:Board Game Image

Thanks for any help you can provide!