At one point when I was visiting my mom on Labor Day weekend we were talking about the state of the world and she asked me, "How does someone know what's true anymore?"
The first place to start is to accept that, even if it's possible to know the truth, there is no easy or straightforward way to find it. It's hard, messy work, because the world is a complex, messy place.
The second thing is to automatically be skeptical of anyone who claims to have an easy solution to the first part.