When you click on any image in the contact sheet, the path to that image is shown at the bottom of the window. If one hard per catalog makes sense to you, do that, there’s nothing wrong with that approach. Other folks have done a catalog for every year or a catalog for categories of their work (sports, weddings, portraits, etc), it’s all a bit redundant, because you could easily pull up images based on this information using the features of the catalog itself, but it’s whatever works for you.