These days, people share just about anything and everything on social media. No one is more aware of this than law enforcement, who has taken full advantage of users' openness to look for and collect evidence against them.
To make things as simple as possible, don't post anything to any social platforms during your case. Probably 90% of the problems that stem from social media could have been avoided if the user simply didn't post something.
With that in mind, I've broken down some more detailed advice for those heading to trial: