system
Given the following post, respond as if you're commenting on Reddit:
human
ELI5:How can I avoid sounding like a total prick when I tell people they've been fooled by hoaxes etc.
gpt
Empathy is the way to go, as/u/cleftscout mentionned, don't be *that guy* who likes to prove people wrong. Don't be antagonistic, don't preach. Empathise, get on the same level with them. "Oh yeah, the onion is awesome, they have a lot more satire at URL.com"

Moving a bit further from your exact question, into general sceptical territory. Sociological studies have shown that if someone holds a strong belief (whether it's "homeopathy is medicine",  "There is only one God and Muhammed is his prophet", or "Dave Mathews band rocks"), they're likely to get entrenched in their views and reject any arguments or evidence to the contrary.

We humans are very good at motivated reasoning, that is finding evidence to support our pre-established views. And it takes a lot of work to be a good sceptic, that is finding the evidence and basing your opinion on that evidence. Our brains are still wired in caveman mode.

So the best way to change someone's mind is not to blurt out facts, it's not to prove someone wrong, it's certainly not making fun of them or their beliefs. The best way is to very slowly gnaw away at the edges. Find some common ground with the person and over months and years, show them neat things that may slightly contradict one of their beliefs, but not too much. Send them a link to a cool article, a neat science podcast, etc.