How does printing from film work?
And how does one do these X-large prints?

First you need to take a picture on film and develop it. As a result the film turns into a negativ, in this case it's a large format (8x10) one, which gives loads detail:

Next you put it in a projector (enlarger) and project it onto light-sensitiv paper:

The print processor developes the picture. The process is not un-similar to the one used for the film. here it comes:

^{Disclaimer: This is all super-high-end x-large stuff. You can do analog much simpler than that, the process stays the same.}

^{btw.: I skipped all the boring steps.}

^{*gallery print size: 80cm x 100cm}

^{**[Repost] After posting this picture in my early days on steemit, almost a year ago, I realised that my audience was very small then (~50 followers). I now repost some of the best pictures I made to an audience of 1000+.}