These are great days for learning about the nature of reality, the spiritual war of God and creation under assault from Satan and moral inversion; and that is what this mortal life is for.
But it is possible, frequent, to feel overwhelmed by the task of discernment... Yet to feel overwhelmed is to fall into a snare.
In reality things are made easy for us; if we maintain a proper (eternal) perspective, and stop trying to analyse and strategise about the specifics of this-worldly effectiveness.
What we need to do is simple, albeit difficult. It is simply: to recognise evil when it impinges upon us.
We don't need to know about evil that is abstract, absent, elsewhere, to-somebody-else we don't know or love. It is only that evil which actually impinges that we must know.
So, the task is two-fold: the first to be aware of evil, to know it; the second to reject it.
Evil knocks on our door, and asks (or demands) to be invited-inside. All that we need to do is to say No. Because evil cannot enter without permission.
Naturally, evil adopts disguises - It might come in the form of a kind old lady, a sexy youth, an expert professional, a charming wit, a pitiful wreck of a person. Evil might be in words, symbols, music, landscape, architecture... pretty much anything. Even worse - evil often regards itself as good, has a 'clear conscience'; and sees goodness as the 'real' evil!
But the thing is - We Always Know Evil.
We all have an inbuilt, spontaneous, sensitive evil-detector; active 24/7 and that penetrates all disguises; an alarm that sounds when evil impinges, when evil requests an entry.
Therefore we need not care about all the disguises and deceptions of evil - Our simple task is just to become aware of that inner alarm, in our heart; to recognise its warning; and to respond.