Instructions
Decide when your story will take place in the "Twilight" saga. Which book would it fit in with best? The first, when Bella and Edward meet? The second, when Edward leaves and Jacob makes his move for Bella's heart? Or the third or fourth when Bella and Edward vow to be together for the rest of their lives? Of course, you can always veer from the traditional "Twilight" plot line and create your own story altogether.
Outline your story. The best way to keep your ideas in order is to commit them to the page. Create a word processing file with multiple pages. Label each new page with a different idea for your storyline. Under each header, compose five or six ideas to carry your plot along. Rearrange your thoughts as you go along to ensure flow in your story. For instance, if you are writing a story set at Forks High School, you could set the scene at lunch with Bella, Edward, Rosalie, Alice, Emmett and Jasper -- the vampire coven siblings -- and Bella's human friends Mike, Jessica and Angela.
Write your story. Begin with the first part of your outline, and put your story together bit by bit. Write about how Bella and Edward's love affair is the center of attention and the main discussion at the lunch table, while Mike Newton stews in the corner, plotting how to get Edward out of the picture. Continue your plot until you have incorporated each part of your outline that you feel belongs in the story.
Proofread your story for clarity and interest to make sure it remains "Twilight"-related. Submit it to a fanfiction website for feedback from your fellow Twi-Hards.