Your participant casts a spell, and you demonstrate it beginning to work.
In this 32 page PDF, Lewis provides a specially designed magic square, that’s NOT a ‘magic square’. Instead, on a folded slip of paper that you can carry in your wallet, is a hand-drawn square with different types of spells, intentions or points of focus written around its edges, words like love, growth, insight, change, power, and so on. In having your participant merely THINK of one of these topics in the form of a simple ritual, you will know EXACTLY which one they have chosen.