Sometimes, you just have to ask people what they want. And sometimes, since people are really bad at getting out of their own way and telling you exactly what they want, you have to make them figure it out for themselves.

Thus is the story behind Facebook’s new news feed, which is currently rolling out to users very very slowly. Apparently, “user experience researcher” Jane Justice Leibrock used psychological and anthropological methods to figure out what Facebook users actually wanted in their news feeds.

And she used a bunch of index cards and a big white wall the do it.

First, she asked people about the biggest problem with their news feeds. A lot of people said “clutter.” It was quickly determined that “clutter” didn’t really mean that the visual space was busy, but that users were unhappy with the types of content that they were seeing from friends and pages.

That’s when she busted out the index cards and sticky notes.

From her blog post on the Facebook engineering page:

We came up with the idea of multiple feeds, each with its own focus on a particular topic, type of content, or type of friend. It was a good start, but crucial questions remained: which feeds to offer, and which stories to put into them? Those answers required a second round of research.

I didn’t simply ask people which feeds they’d like to see, because as any user experience researcher knows, it’s very difficult for people to predict what they’ll end up liking. Instead I needed to come up with a way for people to show me — not tell me — which feeds would be valuable. I chose a method known as a “card sort,” which researchers usually turn to in order to understand how people mentally relate different topics to each other. But as we often do in research at Facebook, I adapted the method for a different purpose: to get people to reverse-engineer the feeds they’d find interesting. I gave each participant a stack of recent stories from their feed, printed out on paper, and asked them to pick out the ones that interested them and discard the rest. Next, I asked them to sort the remaining, interesting stories by putting them into piles separated by what they liked about each.

Apparently, there were overarching themes to how people organized the stories: photos, posts from close friends, and (surprisingly to Leibrock) posts related to their interests.

And that’s where the multiple feeds were born, from this reverse engineering. Check out the full post here if you want to go a bit deeper into Facebook’s thinking behind the new news feed.