Flashbacks, when skillfully used, can focus on a theme or an important element in a character’s backstory. When done poorly, they’ll be an interruption and can be confusing.
How will you know if it’s good enough or not? If you take it out, will the story still be complete and whole? Make sure your flashback has strong verbs. When you’re ready to go into a flashback, add a strong sensory detail that sparks the memory.
To return to the present time, go back to that sensory detail.
Exercise: Today, make a date with yourself to note your own flashbacks in YOUR life. When do they occur? What seems to cause them? What brings you out of them?
Reading Exercise: As you read them, note when they are done well.
Writing Exercise: Have you used them in your own stories? Do they need to be improved? Attempt to rewrite them if they do. Or write a story and create a flashback in a scene