Many new teachers struggle to create effective instructions. On our courses we say that all classroom task instructions should start with a verb. For instance, ‘sit down, stand up, do exercise 6’ etc.
It’s a simple but really effective rule. It takes out all embedded language, complex polite forms, and reduces rephrasing. Some trainees find the directness feels rude but as a trainer you can demonstrate that tone and attitude can convey politeness and that for learners the priority is to understand the task.