How do I create a page that links to all galleries?

I’m looking for a tutorial or some information that shows me how to take all of the galleries I’ve included in individual posts, group them by date, and include them on a Page of my WordPress site. In short, I’m trying to pull off what Matt has pulled off here: https://ma.tt/category/gallery/

I created a Gallery category on my blog, but instead of presenting the photos the way it is on Matt’s site, I see all of the photos contained within the gallery on the page.

Help?

Thanks in advance!