I'm writing this as a guideline to both myself and others, seeing just how low effort the crushing majority of fanfics on this app/website are. So many fanfics could be fixed by simply googling "How to make a good story".
This is me searching the internet's top recommended searches about how to make good fanfics, fight scenes, romance, and harem. A compilation of them plus some of my own takes on them. Feel free to use this unrestrained. I beg you to do so.
Most things here aren't mine, and I will not take them as mine.
Since most fanfic sites don't allow links, here are the titles of each website, title, and search I used to make this:
[Fanfic]:
HOW TO START WRITING FAN FICTION (Bookriot website)
So You Want To / Write a Fanfic (Tvtropes website)
So You Want To / Write a Good Summary (Tvtropes website)
7 Tips on How to Become a Great Fanfiction Writer – Guest Post by Hayley Zelda (Wordmothers website)
8 Pro Tips to Becoming a Successful Fan Fiction Writer (Cosmopolitan)
How do you write good fanfiction? (Quora)
How do I write a good Y/N fanfic without it becoming cringy? (Quora)
A Beginners guide to writing fanfiction (Deviantart)
5 Mistakes to Avoid When Writing Fan Fiction (Writingtipsoasis)
-=-
[Fight Scenes]:
Tips for writing fight scenes? (Reddit)
How to Write Fight Scenes (wikiHow)
How to Write a Convincing Fight Scene (nybookeditors)
Tutorial: Fight Scene (Wattpad)
-=-
[Romance]:
What are some good tips for writing a romance fanfic? (quora)
-=-
[Harem]:
The harem setting: why it's not an excuse to write a crappy story (royalroad)
How to create a proper Harem story (DeviantArt)
Basic ideas how to create a good harem story. (royalroad)
So You Want To / Write a Harem Anime (tvtropes)