It's hard to answer this, as we work on many different products at Facebook, from VR to News Feed to helping businesses connect with customers to providing services in emerging online markets like India, and depending on the context, audience, and life-stage of the product we are working on, our design process is different.
However, no matter what we work on, we try and make sure we are doing a few things:
- Understanding who we are designing for: Over a billion people use Facebook in countries all over the world, and the "average Facebook user" is no longer a meaningful concept. When we design products now, we try and have a clear understanding of what kind of person we hope finds value in what we are building, whether it is people in particular markets like Japan, Brazil, or the U.S., people in certain life stages (like high school teens, parents, or people who have just moved to a new city), or people who have particular needs (like connecting with old friends; being a part of a community who discusses a particular topic; knowing what their friends are talking about, etc.)
- Understanding the problem we are trying to solve: We try to clearly articulate what problem we are trying to solve, and why we think it is a real problem.
- Understanding what success looks like: We try and imagine, "Okay, if we worked on this thing, what would it mean to do a good job? What would be the change in the world from where we are today?"