In this video, the teacher provides guidance on how to ensure that anecdotes in writing stay focused on the given prompt. They emphasize the importance of reviewing and revising your work to make sure it answers the prompt effectively. The teacher walks through an example of a persuasive letter about getting a pet, highlighting the process of checking each anecdote for relevance and crossing out unnecessary details. By following these steps, students can ensure their anecdotes support their argument and strengthen their overall response.