How to have an index display post thumbnails?

hehe kind of like the question I asked yesterday.Maybe you could try working off this theme https://5thirtyone.com/archives/886. I didn’t use the theme though to display the thumbnails.I just added a few lines of code which wasn’t too hard at all so I think you should really take a look at this short tutorial.
https://markjaquith.wordpress.com/2009/12/23/new-in-wordpress-2-9-post-thumbnail-images/