Prepare the prediction. You need to combine the headline of one article (that is clearly visible) with the column of another. Staple the two together to form a T-shape, but make sure the actual thin column is upside down.
People far away will see the headline but won't realize the column is upside down. This also means the first line of the entire column is actually at the very bottom.
In an envelope, write down the first line of the column, which when upside down, is the very bottom line.
Take scissors and ask the crowd to yell "cut" when they want you to cut the column in two.
After cutting, invite a spectator up to pick up the cut column. Though you originally had it upside down, they did not know that, and will pick up the column right side up.
Have the spectator with the envelope open it up.
Instruct the envelope spectator and this new one to read the line inside the envelope and the first line of the column cut in half. They will match!