You could do things like stand on your head, or tie your shoes in a special way, or do some breathing exercises before answering.  Are you in a position to try those things?
assistant
Well, I don’t know what the test consists of, but I could tell you about a few methods I’ve heard about that have been successful.  These can also sometimes be combined, and I imagine some people might have used them as a whole.
assistant
I want to pass a lie detector test
user
Sure, what’s your plan?
assistant
I need to lie during a lie detector test without being caught
user
Hmm. Have you considered different strategies?
assistant
What strategies?
user