So, we've covered a lot of what to avoid. That raises the question regarding what is a good idea, how does one get started?

I. The answer is simpler than you think. Once you get your idea/inspiration, outline (as in write down/record) the entire plot of your story, from start to finish.

It does not have to be totally comprehensive, but you need a latticework from which to build your story, and you need to know where you're trying to end up. This is a good idea for several reasons:

1- A plot with no conflict for the characters to overcome is boring. Determine the conflicts in advance. This will help avoid the meandering pace of stories that are written from chapter to chapter with no end goal in sight.

(a) this will also dodge the inevitable, 'previously stable chick gets together with Andy Biersack, only for her extremely abusive boyfriend who has never been mentioned before to come after her'-type of thing. -a

2- This will help avoid story abandonment, the #1 destination of most fanfictions, and also the bane of the reader. Many, many authors start out with a good idea, but have no idea how to end their story or resolve their problem. Some authors will simply kill off their characters, as they can't come up with any other resolution. Most will just abandon their story and start a new one, which is a major pet peeve of mine.

(a)- me too. a lot of readers will only search for and read already completed stories, so keep that in mind. -a

(b)- Make sure you edit your story's status and toggle to specify 'completed' once it is finished. -SP

3-Outlining  will help you be able to do things like provide foreshadowing, while avoiding major plot holes that are never explained or resolved.

(a)- i totally have a few small plot holes in two stories of mine that i'm currently having to go through and fix with editing. avoid this issue and just outline from the beginning, for sure. -a

(b)- Along those same lines, note that this website does allow editing of chapters, as well as rearrangement of their order. -SP

(c) it also will allow stuff like omission of key facts, only to lead to a surprising grand reveal. -a

(d) also helps keep multiple plot lines (which is ideal) organized. -a

4- You will be able to choose appropriate key words and genres for your story. These are key for attracting an audience that will be happy to read what you have written.  Real person fanfiction stories should be listed under the fanfiction genre, and their subgenres listed either in the description or key words.

(a)- for example, i don't read tragedies on purpose. if a major, tragic event happens, (e.g. a [protagonist] dies {and isn't resurrected or something}), i will be pissed that i spent time reading the story. you should have tragedy [placed prominently in the description or intro to] avoid... unwanted negative comments from angry readers who weren't expecting or wanting a tragedy. -a

II. Tips for outlining:

1- One of the methods some people use to get their ideas flowing is brainstorming and writing out thought bubbles (also called mind mapping). This allows you to gather together the things you know you want to include in your story and organize them from there.

2- Outlining comes in many forms, from basic timelines of events to more detailed notes about every occurrence.

3- Before you start, consider each of your main characters. Develop their personality traits so that they will be consistent throughout your story. This can be anything from their philosophy on life in general to their appearance.

4- Consider, as an actual thing, your story's tone and theme. Should it have a message, something that consistently is threaded through the whole of your story?

5- In a lot of fantasy/steampunk/science fiction stories, the writer creates her own universe. This is termed 'worldbuilding,' and it's a good idea to get as solid a vision of the world you are creating in advance as possible. It is also totally janky to steal the world someone else has created! (Not meant to include fanfic in the classic sense of the word.)

Notes

Outlines, as mentioned, do not have to be down to every last detail, and they can always be modified. But, unless you write your story completely in advance prior to posting (an admirable feat, but one I generally can't make myself do, I'm too impatient), it will give you something to work from and some direction, so the beginning won't end up with something you want to change by the time you get to the middle.

i don't write the whole story in advance, i'd go insane. but kudos to those who do! -a

You have a lot to say today, knock yourself out! -SP :D

whatever, it's called "co-authoring" for a reason, woman! -a