Just some stuff to chew on

from an indie author who's published 4 books and written 20+, as well as 400k in fanfiction (who is also a professional beta reader who encounters the same issues in my clients' books over and over)

show don't tell is every bit as important as they say it is, no matter how sick you are of hearing about it. "the floor shifted beneath her feet" hits harder than "she felt sick with shock."

no head hopping. if you want to change pov mid scene, put a scene break. you can change it multiple times in the same scene! just put a break so your readers know you've changed pov.

if you have to infodump, do it through dialogue instead of exposition. your reader will feel like they're learning alongside the character, and it will flow naturally into your story.

never open your book with an exposition dump. instead, your opening scene should drop into the heart of the action with little to no context. raise questions to the reader and sprinkle in the answers bit by bit. let your reader discover the context slowly instead of holding their hand from the start. trust your reader; donn't overexplain the details. this is how you create a perfect hook.

every chapter should end on a cliffhanger. doesn't have to be major, can be as simple as ending a chapter mid conversation and picking it up immediately on the next one. tease your reader and make them need to turn the page.

every scene should subvert the character's expectations, as big as a plot twist or as small as a conversation having a surprising outcome. scenes that meet the character's expectations, such as a boring supply run, should be summarized.

arrive late and leave early to every scene. if you're character's at a party, open with them mid conversation instead of describing how they got dressed, left their house, arrived at the party, (because those things don't subvert their expectations). and when you're done with the reason for the scene is there, i.e. an important conversation, end it. once you've shown what you needed to show, get out, instead of describing your character commuting home (because it doesn't subvert expectations!)

epithets are the devil. "the blond man smiled--" you've lost me. use their name. use it often. don't be afraid of it. the reader won't get tired of it. it will serve you far better than epithets, especially if you have two people of the same pronouns interacting.

your character should always be working towards a goal, internal or external (i.e learning to love themself/killing the villain.) try to establish that goal as soon as possible in the reader's mind. the goal can change, the goal can evolve. as long as the reader knows the character isn't floating aimlessly through the world around them with no agency and no desire. that gets boring fast.

plan scenes that you know you'll have fun writing, instead of scenes that might seem cool in your head but you know you'll loathe every second of. besides the fact that your top priority in writing should be writing for only yourself and having fun, if you're just dragging through a scene you really hate, the scene will suffer for it, and readers can tell. the scenes i get the most praise on are always the scenes i had the most fun writing. an ideal outline shouldn't have parts that make you groan to look at. you'll thank yourself later.