Resting Bitch Face is usually a lingering anger micro-expression with pinched eyebrows and vertical lines between them. Vanessa Van Edwards teaches an "up face" technique: slightly widen your eyes and turn the corners of your mouth upward to look engaged and awake, especially on camera or while listening.
Chapters
You know if you have RBF if people often ask you questions like, "Are you okay?" "Are you mad?" "What's wrong?" So the most common RBF that I've seen is when we're in rest, we're actually holding the anger microexpression or part of the anger microexpression. So remember, anger is when we pinch our eyebrows together and these two vertical lines appear. The problem is people often think like this. Here's my solution for you. So first, it's good to know what people are seeing when you're at default. The second thing I want you to think about is when you know people are watching. So when I'm on camera and I'm just listening or I'm just waiting, I do what I call an up face. So here's my resting face, a little sad even though I'm totally neutral, and here's my up face. So I open my eyes a little bit wider and I just turn the corners of my mouth up. It's not a smile, it's not an expression other than I'm awake and I'm listening.