One of the classic forms of mind reading is the center tear. With a center tear, you can get the secret information that a Participant has written.
Almost all of the center tears require a pre-folded billet which the Participant needs to re-fold the same way after they write down the secret information. The "Butterfly Center Tear" (BCT) is my solution to a no pre-fold center tear. With BCT, you can now hand a flat billet to the Participant and still be able to perform the center tear to peek the secret information. You can also use this method as your backup center tear in case the Participant did not comply with the billet pre-fold.