How to Write Flashbacks
Past experiences are like salt. Just enough will add perspective and an important backstory to your writing. Too much will make the entire narrative difficult to comprehend.
The key to employing flashbacks is to make sure you’re satisfying both of these requirements:
Never introduce a flashback without a "trigger" beforehand. Let one character, for instance, explain their story. Or have your protagonist's sense of smell triggered a recollection? Readers will tend to roll their eyes and question why the author is dumping it on them if you don't take some care in explaining why the flashback would occur inside the plot. Instead of distracting from or making the flashback appear like something, employ a trigger to make it feel natural.
Don't ruin the surprise:
If your book's mystery is solved by page 10 thanks to a flashback, there's not much purpose in continuing, is there? Flashbacks are used in The Three Apples to both provide background and to take away from what the reader believes they already know. Don't start a full-fledged flashback until your reader is prepared to understand the complete enigma. Prior to that, simply add a small amount to heighten the intrigue—but not so little that the reader becomes confused.
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