1. I'll try my best to simplify it. So first things first you need an idea before you can do anything. I'm going to use sweet n' sour as I walk through this so spoilers if you haven't read it. Also I wanna say MOST of mu fics don't follow this structure, sweet n' sour accidentally had a solid plot that hit the key elements lol.

Idea: In a post-apocalyptic setting with an ecological disaster causing the omegaverse, Jisung, a city-dweller with OCD, steals from Minho's pack and is caught. He pays off his debt through free labor, discovering a life outside pure survival.

This is where I go in and describe the general premise of the story, highlighting some key elements. More specifically I focus on the character's problem, want and need. Every POV/important character that will have a complete character arc needs these three things. In Jisung's case.

Problem: He is caught stealing and has to work off his debt
Want: To belong in his pack/be accepted
Need: Love/acceptance

Generally the need is one of ten universal things. "Love and acceptance" is very broad after all. Another way to look at it is with the following three questions:

Problem: What stands in the character's way? (Jisung's debt)
Want: What does the character think they need to be happy/fix their problem (pretty much always external)
Need: What does the character actually need to be happy/fix their problem (internal)

Note: a character's problem, want, and need change throughout the story. It doesn't always have to be one set for the entire story.

Once you have that figured out this is where I write down everything I want in a story in my notes app on my phone. I just think of every scene/dynamic I want to include. For example in Sweet n' sour I wanted a free use scene (that didn't happen), but I also wanted him being trapped in the haze, the secondary gender reveal, the cellar, Jisung's heat, the puzzle sorting (all of which did happen). I usually plan the story out in my head for months before doing this part so I usually am overflowing with ideas.

When I have a solid grasp of the vibes. I use the seven-plot structure and match to the key elements from my brain dumb. I used to use three-act plot structure (beginning, middle and end) but personally it felt too vague. As a warning, most ff's start on the inciting incident and skip the "establishing normal" because we already know the characters.

~ this is an important scene
[ ] this is for things that happen in between the important points

~ Hook: First page where you're establishing character, setting, and possibly the first signs of the problem.
[first 10% of a story]: establish what is normal for the character. Who are they? What do they want? Why haven't they achieved it? What is standing in their way?

~ Inciting Incident: What triggers the character's life to change? This is why the story starts where it does. This is also known as the call to action, so a character chooses a different path in exchange for thinking it will solve their problem
~ Pinch point 1: First plot point that adds pressure to the character. It usually reveals some new information and adds stakes to the story.
[fun and games]: put whatever you want here. keeping in mind everything that has happened prior and where the character continues to grow and develop.
Midpoint: The trajectory of the story drastically changes. Either a key point is revealed or the dynamics of the characters change. This is done so now the character must keep moving forward with a new perspective. This should challenge everything that the character believed up to this point. This is also when they should start doubting their want and their need should be more prevalent.
Pinch Point 2: The stakes are raised even higher. They might have realized what they truly need but either be unwilling or unable to achieve it. This should push them toward changing their worldview and in turn growing as a character. This is also where you oftentimes see third act breakup.
[rising action]: pressure is building as the character struggles with what to do. Knowing if they make the wrong choice they could lose everything or return back to where they started. This also oftentimes enters the lowest point of a character's journey.
Climax: The scene that decides everything. The character makes a choice or accomplishes what they need to finally fulfill their need. They don't always get what they want. They don't even always fix their problem. But as long as they get their need they have grown enough to deserve it.
Resolution: the fun bits afterwards where they live in the aftermath.

This is assuming a happy ending (it's all I write) but in some capacity it can still be sad. A character can get what they need and lose everyone they care about.

Sweet n' sour
Hook: Technically the first very telly paragraphs but that's horrible practice for published books
inciting incident: Jisung is captured.
Pinch point 1: Jisung agrees to work off his debt
Mid point: Jisung is an omega reveal
Pinch Point 2: The elders requesting Minho mate with someone else and put pressure on the pack
Climax: Jisung's breakdown on the kitchen table (although it was anti-climactic
Resolution: Jisung and Minho mate

From there I flesh out my outline. I go through in order of the scenes I want to add, usually getting more vague with the later ones but making sure I have all the stuff in between and am hitting the seven key scenes. I also try to add important character growth scenes and character relationship moments. All character relationship growth should be on screen. So if Minho and Jisung have a bonding moment that makes the closer, I try to add it in to this outline. I sit on this outline for a few weeks making sure it's good and editing changes as ideas come to me. This would also be a good time to write up the character's backstories but I'm more of a pantser when it comes to that. I go with the flow :)

Lastly from here, I just write. I usually write in order and the recommendation is to write a few scenes to get a feel of the characters but I just write them out of character and then rewrite the first few scenes in the next draft because I feel like it's a more natural progression for me personally. Also when I write, I need to see a scene in my head before I can write it down. So I plan the future scenes in the shower or as I'm falling asleep. Thinking up some dialogue or character interactions.

Then as I write I change the outline but generally keeping the seven plot points in mind, knowing I want to hit them (or I'll change them). It's also good to give side characters problems/wants/needs but they don't all need full character arcs. Giving too many of them full character arcs might actually take away from the main character's growth.

Hope that helped! It's also important to remember that not all plots are made the same and it's good to know the rules when you break them, but you should definitely not stick to it because it's the "right way" to do it. I write mental health plots which vary vastily from action plots with antagonists because oftentimes my characters are their own antagonists. Jisung's biggest antagonist was himself and his self-sabotaging.

1. ah yes "research". Unfortunately, it's kinda personal experience too. The PTSD. I also write so much about mental health, I'd be sad if it didn't come off as realistic. Also yes, they will be okay (peep the angst with a happy ending tag)