A good trick is to read manuals but never let on that you read them. That way when you are troubleshooting you look like a genius.
“Maybe we should check the operating water pressure. I feel like it should be at least 3 bar”
My other favorite trick is to put small parts into my pocket during disassembly. Then during re-assembly when everyone is in a panic looking for the parts, you can play the hero by “finding” the parts.