Let's continue by considering your own language as a teacher. Your voice is your main searching aid. You can actually yconsciously use its pitch, tone and pace to underpin the shape and changes of the lesson. Do you drop and slow your voice when moving from a lively passage to a quite one?
As we've said, the lesson has its story. This is what your plan is based on. We will do A; this will enable us to understand something. B; will be defined in a transition and then carried forward into the next activity. C; it's the carrying forward that counts. There is a thread, not a series of seperate activities. If you have a clear and simple story, you have a coherent lesson.
Obviously,then, pupils are most likely to make sense of the lesson if they understand the story too.