That you would even ask this question suggests to me that you haven't done your homework and should not even be considering using polygraph countermeasures.

Note that there are two types of questions the answers to which are known to both examiner and examinee: irrelevant questions (such as "Are the lights on in this room?") and probable-lie "control" questions (used in some polygraph techniques, most notable the "Test for Espionage and Sabotage" used by the Departments of Defense and Energy).

Irrelevant questions are unscored. Polygraphers don't expect to see reactions to them, and they sometimes tell the examinee that they're "control" questions in a deliberate effort to misdirect examinees who might be considering using countermeasures. Manufacturing reactions to irrelevant questions won't help one to pass a polygraph "test" (and might lead to an accusation of countermeasure use).

Probable-lie control questions, on the other hand, are scored, and one would want to augment reactions to them to protect against the risk of a false positive outcome.

See Chapters 3 & 4 of The Lie Behind the Lie Detector for more about polygraph procedure and countermeasures.

As we note in The Lie Behind the Lie Detector (4th ed.), it's normal for people to make minor admissions to probable-lie "control" questions (p. 98) and it's okay to do so (p. 128).