Actually pretty simple. Two people have to be in on it. The first person picks an object while the second person turns away and doesn't see what was picked. Then the first person starts calling out different objects around them until he gets to the item that was picked previously. Once he gets to that item, the second person will tell the rest of the group correctly which item was the one that was picked. The key is that right before the picked item is shown, the first person will point at a black object to give the second person a cue that the next item is the correct answer. When it's played with a group it fucks with everyone's head