Step 4: Embracing Scepticism is all about cultivating the art of questioning your own certainties.
For the past 3 steps, you've been building up to this moment, when you're supposed to stop believing your own hype and start doubting everything.
Here's a simple exercise for you: take a piece of paper, write "I don't know" on it 50 times, and then stare at it until you start to feel like you're losing your mind.
When you're done, go to the next step: Step 5: The Sceptic's Toolbox.