While it’s possible to fake a test, it’s not as simple as most would like to believe. The main ways are drugs (apparently ruled out), an abnormally high baseline (which can be spotted by a decent examiner) and by being a psychopath (how a guy like Ted Bundy was able to pass).
There is a reason that polygraph tests are commonly used by law enforcement even though they are generally not admissible in court.
You don’t have to be a zen master. Every test has control questions — something like “have you ever taken office supplies home?” that provoke a guilty response. Learn to spot the control questions, put a tack in your shoe, and you can generate a stress response to the control questions. That way, you can mask the lies.
Bill and Hillary come to mind