You should read your work aloud. Definitely. When you’re alone, when you can’t be overheard, speak the whole thing. Don't mumble or whisper it under your breath. As though you were reading it to someone, which you are (yourself). It will help. It is a little tedious, maybe even excruciating. It will help.
But there are some drawbacks you need to be aware of.
When you read the text to yourself you will be able to spot basic errors. Typos and missed punctuation. Sentences that don’t make sense or you forgot to finish. Sometime you will have written a line one way, then decided on another way, and somehow managed to leave them both on the page. Just the way it sounds and the feel of the words in your mouth will tell you when something isn’t quite right.
However, when you write, you think of what you mean, then you choose the words that convey the meaning.
Meaning —> Words
When a reader reads they take the words in first, then extrapolate the meaning.
Words —> Meaning
When a writer reads his own work, this happens:
Meaning —> Words —> Meaning
The writer already knows what he meant so he doesn’t get the experience the reader does. When it comes to reading your own work it is very easy to attach meaning that you intended the writing to have, but never actually put on the page. This is especially true of dialogue.
When you read out your own dialogue you know what the character means. You naturally say it in that intonation and attitude. Even if the punctuation isn’t there or the implication is ambiguous, you will say it how it is meant to be said. The reader does not have that advantage and will either be unsure what the character means, make a lucky guess, or assume the wrong thing.
You have to be careful with dialogue. Don't rush through it assuming your intent is obvious. It isn't.
The way to fix this is either to rely on critique from a third party, they will spot the probelm instantly. Or by being aware of this possibility and looking at dialogue not only how you intend it, but how it might be interpreted. It’s not that hard to do if like me you go over the same text over and over until you can see all its additional meanings, some of which you might even want to keep.