I see writers asking all the time how to stick with a project. They get a few chapters in and things die out. They don't know what to do with it, or they find their excitement for the story fades away and leaves them unmotivated to continue. When I ask these people how they prepare for their story, the most common answer I get is "Oh, I just get the idea and start writing." Sound familiar?
I've been in the same boat. In fact, despite desperately wanting to be an author since I was 9 years old, I could barely finish a story for years, let alone get anywhere near publishing it. It wasn't until I was 17 that I came across the Snowflake Method of outlining and decided to experiment with it--and proceeded to write the entire first draft of Dreams of Otherworld, what would go on to be my first published novel, in just over a month.
Now, the Snowflake Method isn't magic. Everybody has a different process and is wired a different way, and if you're happy throwing yourself into an idea and seeing where it takes you then more power to you. But if you find yourself struggling to figure out what direction to take your story, or with getting yourself to keep writing beyond the exciting few days of starting, then I advise you try it out. It may not be the method for you, but it may just solve your problems, or at least set you on a path to find a method that does.
Also keep in mind that many of the steps of this method do not have to be done in the order posted here--or done at all. If one doesn't work for you or works in a different place feel free to reorder or adjust them to suit you best.
The Snowflake Method is named so for the way you build up your story before writing it--starting with one simple piece and adding more and more to it until you have a fully fleshed-out plan. Like the image to the side shows, you add increasingly more intricate, detailed bits onto the basic shape of an idea. While that can be done in a dozen different ways, the official method is broken down into 10 steps.
Step 1: One-Sentence Summary
The first step of the Snowflake Method is to boil your idea down to its essence. The idea behind this says that it's critical to understand the core of a story, and this forces you to nail that down without getting lost in all the other elements. This one sentence should sum up the most basic idea of your story, and ideally is kept under 30 or so words and avoids any names.
Examples: A boy discovers he's a wizard and is sent to attend a magical boarding school. (Harry Potter and the Sorcerer's Stone)
Four siblings discover a magical world hidden beyond a wardrobe, ruled by an evil witch. (The Lion, The Witch, and the Wardrobe)
When she goes to visit an ailing relative, a girl discovers a hidden faerie kingdom and befriends its prince. (Arcatraissa)
Your one-sentence summary will serve to give you a direction to move forward from and focus your planning.
Step 2: Paragraph Summary
With the core idea down, you can move on to expanding it into an actual story. This summary should follow the entire length of your story, beginning to end, but kept to one paragraph in length, meaning only the most basic, overarching ideas of each part. If you're using the traditional three-act structure, this summary is most easily done in 5 sentences, but if you're doing something else you can adjust it to suit your needs.
Sentence 1: The set-up. How things start out--who is your protagonist, where are they at the start, and what is the expectation before things change? (If I was using Arcatraissa for this, I might write something about Cassie's family intending to visit her ill Aunt Julia for the summer, and Cassie's initial feelings on this plan.)
Sentence 2: The inciting incident. The event that interrupts the status quo--how does it happen, and what is your protagonist's reaction to it? (In Arcatraissa, this would be Cassie meeting Tae and discovering faeries are real.)
Sentence 3: The first disaster. A brief summary of what happens following the inciting incident, and how things change yet again. Does something happen to raise the stakes? Does the protagonist discover something shocking? Is a plan interrupted or not go as expected?
Sentence 4: The second disaster. Similarly to sentence 3, this should be a summary of what happens between the first disaster and an event that changes the stakes or expectations yet again. The second disaster most often becomes or leads into the story's climax.
Sentence 5: Resolution. How the climax plays out and the story ends.
Step 3: Flesh Out the Characters
Before writing, you want to know your characters just as well as you know your plot. After all, they're the ones driving most of these events you're writing about. So to make sure all these many pieces you're juggling fit together perfectly in the end, you need to know as much about your characters as possible. For each of your major characters, and even some side ones if you feel it necessary, write a short summary of their arc through the story. This can be done as a bullet pointed list, in prose form, or whatever helps you the most, but it's most helpful to include the following things:
Their goal: What does the character want to achieve? All characters--protagonist, antagonist, or in between--have a goal of some sort, and it's a crucial part of understanding their role in the story. Harry Potter wants to defeat Voldemort. Katniss Everdeen wants to win the Hunger Games.
Their motivation: Also called a character's "why", their motivation is the reason behind their goal. Every goal has a driving force behind it, sometimes more than one, and a motivation often plays into a characters' backstory and makes them more real and relatable. Harry's motivation is to protect his friends and the Wizarding world. Katniss wants to protect her sister and return home. Be sure not to gloss over your antagonists' motivations--they care about things too, whether we agree with them or not.
Internal conflicts: What does your character struggle with, beyond the outside factors going on? Are they unsure or scared of what they're doing, have their loyalties torn, or know something that conflicts with their goal?
Their epiphany (or epiphanies): This is how the character changes through the story. A realization they have or something they learn on their journey. It might change their goal or motivation, or it might be the result of succeeding or failing to achieve their goal. It might result in a new goal to lead into another story. A character's epiphany can came about in a thousand different ways and be anywhere on the spectrum between positive and negative, so let your creativity have fun figuring this out.
Step 4: Expand the Summary
You should now have the skeleton of your story and a good idea of the major characters and events in front of you. Now it's time to add the meat of the story by expanding your summary. Turn each sentence of your paragraph into a paragraph of its own, adding in details, side characters, and subplots so you have a more rounded summary of that section. By the end of this you should have a much lengthier, detailed summary that gives you a solid idea of what needs to happen and how the major events from your paragraph summary lead into one another.
Step 5: Different Perspectives
Now that you have a more detailed summary, head back to your characters and figure out how they each see the events going on. Each character should have their own unique view--they may agree on certain things, but events will ring different to different characters based on their backstories, internal conflicts, and goals. Write up a brief summary of the story from the perspective of each major character, exploring how they react to things and anything they do "off-screen" that affects other events or characters.
Step 6: Expand Again
Jump back to that 5-paragraph summary you wrote in step 4. Time to expand again. Using what you've figured out about your characters and how they fit in with these events, write a more detailed summary from beginning to end fleshing out everything that wasn't explored fully before. It's recommended you have a 3-5 page summary by the end of this, but don't worry if you go over or under. As long as you feel you understand your story well by this point, you should be okay.
Step 7: Refining Characters
We're going back to your characters for this step. You should know them pretty well by this point, but now is the time to sort out any kinks in your planning. Refine their character arcs, write out their backstories, make a chart of their role in the story, figure out their relationships with other characters, or anything else that will help you fill in any remaining gaps.
Step 8: Outline
Using your detailed summary, break the story up into scenes. It shouldn't be too hard by this point to figure out where things need to break into natural scenes or chapters based on the events. Take this list and put it into a spreadsheet, outline, or bullet point format with notes on what happens, who's involved, and any other information you feel you might need. The resulting outline will be, I find, the most useful tool for during writing, to reference as you go.
Step 9: Synopsis
This step isn't strictly necessary, but can be very helpful if you're hoping to go through the traditional publishing process. Take each scene from your outline and expand it into a short paragraph. You'll end up with a draft synopsis you can use for reference as you write, or as a basis for a synopsis you may need to give literary agents later on.
Step 10: Write!
Sit back and admire your hard work before jumping into your first draft. You should now have a solid, well-developed road map to guide you all the way, and your writer's block should be (mostly) eliminated.