Writing tips for long fics that helped me that no one asked for.
1.) Don't actually delete content from your WIP unless it is minor editing - instead cut it and put it in a secondary document. If you're omitting paragraphs of content, dialog, a whole scene you might find a better place for it later and having it readily available can really save time. Sometimes your idea was fantastic, but it just wasn't in the right spot.
2.) Stuck with wording the action? Just write the dialog then revisit it later.
3.) Stuck on the whole scene? Skip it and write the next one.
4.) Write on literally any other color than a white background. It just works. (I use black)
5.) If you have a beta, while they are beta-ing have them read your fic out loud. Yes, I know a lot of betas/writers do not have the luxury of face-timing or have the opportunity to do this due to time constraints etc but reading your fic out loud can catch some very awkward phrasing that otherwise might be missed. If you don't have a beta, you read it out loud to yourself. Throw some passion into your dialog, you might find a better way to word it if it sounds stuffy or weird.
6.) The moment you have an idea, write it down. If you don't have paper or a pen, EMAIL it to yourself or put it in a draft etc etc. I have sent myself dozens of ideas while laying down before sleep that I 10/10 forgot the next morning but had emailed them to myself and got to implement them.
7.) Remember - hits/likes/kudos/comments are not reflective of the quality of your fic or your ability to write. Most people just don't comment - even if they say they do, they don't, even if they preach all day about commenting, they don't, even if they are a very popular blog that passionately reminds people to comment - they don't comment (I know this personally). Even if your fic brought tears to their eyes and it haunted them for weeks and they printed it out and sent it to their friends they just don't comment. You just have to accept it. That being said - comment on the fic you're reading now, just do it, if you're 'shy' and that's why you don't comment the more you comment the better you'll get at it. Just do it.
8.) Remove unrealistic daily word count goals from your routine. I've seen people stress 1500 - 2000 words a day and if they don't reach that they feel like a failure and they get discouraged. This is ridiculous. Write when you can, but remove absurd goals. My average is 500 words a day in combination with a 40 hour a week job and I have written over 200k words from 2022-2023.
9.) There are dozens of ways to do an outline from precise analytical deconstruction that goes scene by scene to the minimalist bullet point list - it doesn't matter which one you use just have some sort of direction. A partial outline is better than no outline.
10.) Write for yourself, not for others. Write the fic you know no one is going to read. Write the fic that sounds ridiculous. You will be so happy you put it out in the world and there will be people who will be glad it exists.