Very similar to a trick I did as a kid, which used the same “jump ahead” method, but requires no memorization. You just need one confederate in the audience. Ask a number of people to write down the name of an object on a slip of paper, one per person. They are asked to fold the paper in half, then in half again, and place the paper in a hat. The confederate has written down a previously agreed upon object, and secretly marked the outside of the folded paper.
The mind-reader picks out any paper except the marked one, goes through some theatrics, then calls out the agreed-upon object name. The confederate calls out “That’s mine!” The mind-reader opens the paper to confirm it’s correct, casually refolds it and tosses it on the floor. The mind-reader now knows a real item’s name, and uses it when he picks up the next piece of paper. Continue until all the papers have been guessed, picking the confederate’s paper last. If anyone checks the papers later, they will all match up to the mind-reader’s guesses.
