I’m only a amateur writer and I have little experience with writing actual novels but a novel is a result and results are always achieved through the same methods. This will not tell you how to make your novel good literature but it will tell you how to apply your writing skills without starting to hate your novel leading to it never being finished.
Love what you do and have fun with it
Unless you are motivated by some external reward such as money or fame, which are usually terrible motivations but good enough for a simple example, then you will start to hate your book if you do not love some aspect of it. Even if you are motivated by some external reward you will still hate the process of writing it but you may force yourself to finish it regardless of your feelings towards it. You need to love some part of your novel and feel passionate about some part of it because only that will make you fell excitement every time you sit down and only that will make you write 5000 words without even realising the whole day has gone by. Writing is supposed to be the entertaining part for the author and making it a chore will not only make you feel miserable but it will also result in you doing half the work at half the quality. Not enjoying the process will make it impossible for you to ever finish your novel and make it good. Fun is the basic foundation necessary for your novel.
Making mistakes is the only way to progress in life but it is especially important whilst writing novels. There is a reason every writer creates a first draft and every first draft is terrible. Stephen King doesn’t write a book in one sitting, allows his editors to admire it without spotting one mistake and then publishes it. A flawed first draft is important because your novel will have flaws the first time you write it no matter how much effort you put into it. I’m not speaking about grammar or skilled writing, I’m speaking about your story. Your story may sound good but until you write it out you will never know how it actually reads, how your ideas fit together and how your characters actually feel. Writing the story with no actual literary value will highlight the flaws within your story. After facing those flaws you will be able to make it a literary master piece with perfect grammar.
If you are having fun then you shouldn’t struggle with writing your story but everyone has moments of weakness. I don’t want you to write 10000 words every day with no breaks ever but as much as you love your project writing it will be work, editing it will be work, developing subplots which you don’t care about will take work. It is within our human nature to ignore things which won’t help our survival meaning that it is within our nature to ignore everything we don’t need to do. We don’t need to do anything. You don’t need to write a book. You don’t need to be a millionaire. You don’t need to have a six pack but that doesn’t make us want those things any less. You will tell yourself that you will do it tomorrow today, tomorrow and the day after until you finally maybe do something on day three but telling yourself you will do something tomorrow when it was planned for today will only waste time.
If you want to make a world war two story and you set your mind on the world war two story hearing that reading a gunfight every two pages and seeing the protagonist massacre armies will not be taken well but criticism will make you better. People are proud and they like to think that they are untouchable no matter how little experience they have so when they ask for criticism they expect endless praise and feel wronged when they receive negative feedback. The harsh truth is no one cares about how the author feels. The writer might be trying to put across a message and shape the story in their own way but if the audience doesn’t enjoy the book then the writer’s work may not even be read. Everyone is your reader and even though not everyone is a writer you want to please readers. If you refuse to take advice you will carry on receiving negative feedback which at some point will cause you to be discouraged and quit.