How do you know what the puppet is thinking? By looking at it. Everyone in the audience can tell you what it's thinking or isn't thinking. You have to tune into what they are thinking. The puppet is thinking whatever it looks like it is thinking.
How do you tune into what the puppet looks like it's thinking? You think the internal monologue of the puppet. You connect the internal monologue to the movements of the puppet. You ask someone on the outside to tell you what the puppet is thinking.
What is the internal monologue? The internal monologue is a progression of thoughts that gets you from one thought to the next to the next. If the puppet is silent then it gets you from move to move. If the puppet has lines then it gets you from line to line. Lines and movements come from the internal monologue.
We were rehearsing Sorrow for the beginning of Act 1 when he wakes up and watches the birds. The inner monologue of the puppet. “morning, morning, it’s morning…" looks up "...Mum, hi mum, it’s morning… oh…" sit’s up "… where are we, where, are we…" stops "… we’re outside, we’re, outside…" to Mum "...Mum, we slept outside Mum, Mum… Did Suzuki sleep outside too…" looks "… Mum Suzuki slept outside too, mental… Birds!" points "... Birds Mum, I can hear birds… where are they? Where are the birds Mum? Where are the birds…" Sees them "… there…" points "… there they are Mum!…” and so on.
Mistakes - the wrong thought with the wrong move eg pointing up and thinking “I can hear them…” Does work because the thought is not specific to the movement. The thought is not what the audience assumes he is thinking when he looks up. We changed it to “Are they up there?” and we were back on track. Why? The thoughts need to be specific. If you look up thinking “I can hear them” you lose the audience because you and the audience begin thinking different things. The point of tracking the thoughts is first of all to know what the audience is understanding from the movements, secondly to control what the audience understands through doing his movements.
And that’s the job. Your inner monologue translates into movements and choices in the puppet which translates back into an inner monologue in the audience's eyes. Once you know how to do that you can lead the audience, mislead the audience, tease them, play with them. Perform.