Grammarly. Reread it multiple times until you go sick from it and edit many parts. So, draft it as many times as you can. :)

Pleasedeteme MaxwellKHA

Thanks brothers!!!!! (´⊙ω⊙`)☞

Must be helpful when everyone recommend word document a lot...
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[unknown] I use Grammarly, but I used to use Scrivener for grammar issues. Both are good.
Other than that, try and get a few beta readers, they can help keep track of the plot. They can also point out if there is something wrong with the flow while reading.

Carciphones_02
Even though it's already been said — Grammarly and proof reading. Not everything on Grammarly will be right, for example, I only take about 50/50 of the suggestions to mind, because some of them don't make sense or something. Also, read books. Books that are either very well polished on webnovel, or published books related to your genre. It allows you to get accustomed to word choices and how to structure certain sentences/scenarios.
That's what I do at least.

Tinalynge how to find a beta reader??
Sorry for the lack of knowledge, I'm not used with all these terms yet!!
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Snowin Thanks!! I will do that!!
(づ￣ ³￣)づ

Carciphones_02 Well the easiest would be to make an author note at the end of your book and say "Hello I need a beta reader. Are you interested in reading the chapters before anyone else, then contact me on XX (this could be your discord, or your email or whatever you are confident with sharing)

I request my beta readers to reply to me every time they read a chapter, and tell me what they think of it. Some of them just says "it was good," and only comments in depth if they find errors, and others comment on every chapter, in detail about every single thing, like "this flows good," "this sentence feels a bit stiff, rewrite it," and so on.

Tinalynge oh!!! I see... Thanks!!