How to be a Devils Advocate
You don’t need to be a lawyer, catholic bishop or contrarian.
You do need to have an open mind, regardless your original perspective, then following these steps:
Step 1: Apply a contrarian approach. What if the issue/task/ideal was the opposite? i.e. “Political correctness (“PC”) is right”, consider, what if being PC is actually wrong?
Step 2: Find evidence in favour AND against the competing propositions.
Step 3: Consider the arguments for and against, work through examples, then ask others of their opinions. By now, you may have found some positives.