If there was a camera on you right now, would you be doing anything differently?
Would you be sitting differently?
Would you been looking at your computer/phone/whatever differently?
Would you not be picking your nose?
Would you suddenly be aware of every move that you're making?
To be as "real" as possible the answer should be "No." You shouldn't change anything. The scene is you reading this post. And this is how you look reading this post. You don't need to change anything.
Throughout the day today, picture a camera suddenly being on you. Just notice, but don't change, what you're doing.