I don't do this often but I needed to make contact sheets out of many folders of an image project I recently finished, to present a PDF of the contents.
Adobe's Contact Sheet II results didn't look good to me (maybe I didn't try hard enough), but I found this free utility from 2008 that still runs under macOS Sierra at least: ContactSheetMaker.
Attached is a screenshot and a sample sheet I made with it, saved out as JPEG. You have full control over the output.
image_96640.pngcontact.jpg
Adobe's Contact Sheet II results didn't look good to me (maybe I didn't try hard enough), but I found this free utility from 2008 that still runs under macOS Sierra at least: ContactSheetMaker.
Attached is a screenshot and a sample sheet I made with it, saved out as JPEG. You have full control over the output.
image_96640.pngcontact.jpg