Each stone is something you want to be true. Tap one and say it a hundred times.
An old stone. It was here before you came.
100
Say the change you want as if it's already true (“I enjoy speaking in front of people”), then say it again, and again.
Each time, the thought runs a little more easily, like a path worn into sand. A hundred is enough for the words to stop feeling like a claim and start feeling familiar, and few enough to finish in a sitting or two.
Each stone's rings are those grooves: one for every ten.