Ends With a Twist
Many readers enjoy ends with a twist as writers skillfully bend the reader's imagination one direction only to trick them with an unforeseen conclusion. However, even an end with a twist must make logical sense. A cleverly crafted finish with a twist will mentally send readers back through the storyline to see if the end really works. One good example of an expertly crafted conclusion can be found in the Sixth Sense written M Night Shyamalan. He keeps viewers distracted by the young boy that can see dead people. It's not until the end that viewers realize the main character is dead. That's why the boy sees him. The end hits with impact, but sends the mind racing back over even minute detail to see if it really works. It's then that viewers realized no one could see the main character. How could we miss that? Good writing.
Fantasy and Sci-fi often present mystical or magical elements that add a surprise factor useful in fashioning a good end. In the first Planet of the Apes movie, viewers enjoyed the magical end as the lead character rides down the beach with the girl he's rescued. They made it and are ready to start a new life. The sense of accomplishment and freedom is short-lived when they come upon the remains of the Statue of Liberty reaching like a mountaintop tossed beside the shoreline. This detail at the end added a thought provoking twist that left viewers thinking long after the theater emptied.
Let It Rest
After you finish the story, don't look at it for a couple of days or more. By that time, a writer disconnects enough to read the text as a reader rather than the author. This is the time to read the manuscript out loud. Take a red pen or highlighter and mark areas that cause you to falter. Don't stop to fix things, just read and mark rough areas (anything that needs work). Keep notes in the margins. If you note a detail lacking at the end, you'll want to work through the manuscript marking plot threads that need to change to make the end work.
As your read the last sentence, you'll know if the end works or not. Does it satisfy? Or, does it seem like something is missing? Did it generate questions or make you realize you dropped a detail? Go back and fix the highlighted areas, put it aside again and go through the process again in a few days or more.
Tune the Beginning and Middle
Once you know you've nailed the end, double check the beginning. Where does the conflict start? What engages the reader—that's the hook, the real beginning. Follow it to the climax. Don't rush it. Let readers savor minor resolutions as you weave details that lure them along in a way that makes them hunger for more and engages them through a blend of heightening conflict and tension. Each detail should be relevant and lead to your perfect ending where every plot thread finds an answer. Your story is ready to submit. The End.