I have heard many people say the same thing. But I have found that, for me, all you should do is re-read the last sentence that you wrote-no more-and start from there. You will have an opportunity to nitpick at it later. Your job, first and foremost, is to gte the whole idea down on paper. The second draft is where you revise. You add things, take things out and adjust what you need to. There should be a break in between finishing the first draft and reading it for the second. You need to basically forget about the story once you’ve written the first draft. Then, with a fresh eye, go back and read through it and find where you need to add and take away. This is just what I do and is what many successful authors say to do. I just follow those who have done it. Hope this finds you in good spirits and still writting.

I’m wrighting a book too i hope yours turns out well,also i’m just saying that it’s good to reread because if you change your mistakes it will make more sense when people read it,but do what u want with your book i’m only 9 and a half :).