Read your story to a friend. If something doesn't make sense, they will probably ask you questions about that part.
Ask them questions about the story. If they understood it, they will be able to answer them.
If they get mixed up, maybe your story was confusing.
Find someone who is a good speller. Have them choose 1 or 2 or 3 words for you to fix yourself. This is good spelling practice for school. Soon your eyes will be able to pick out problem words.
If you are an excellent speller already, have them help you fix the punctuation.
Editing is important because it gets the story ready for the publisher.
