How do I spot and fix continuity errors in my story?

Set it aside and read it anew in a few months.
Or join Critters.

Most authors would use a proof reader to help spot any errors of those sorts. Ask some friends/family members if they would be willing to help you and be objective. Other than that, set the story aside for a decent amount of time, so you forget what you wrote, then re-read it yourself.

Or read it and reread it looking for those errors.

You should definitely have some one else (or more than one person) proof read your story. But before you give it to them, make up a chart that lists categories that would be commonly get get changed, inadvertently, such as names, dates, places, settings, description of someone or something’s look, timeline, dialogue, or whatever else you think might be pertinent. Then, when your friends are reading the story, they can make notations in the boxes when they think they’ve found a discrpancies.

The chart would have the headings at the top, then a bunch of blank boxes underneath each category for the discrepancies to be recorded, with a number. It would be best if the reader had an actual printout of the story (instead of just reading it on the computer) so they can put a red tick mark next to the discrepancy on the actual print out of the story, with a corresponding number and then the same number and the discrepancy would be written into a box under the correct category. That way, you will be able to cross check and go through it pretty quickly.

The mistakes I most often make in stories are when I change a character’s name. If I make a global change of Fred to Jim, I also need to change Fred’s to Jim’s and whatnot. It’s easy to miss if some character calls Fred Freddy somewhere in the story.

I have found it helpful to wait a period of time (it varies according to how much mental energy I’ve already put into it) and read it out loud the next time, with pauses for commas, etc. It might not work for everyone, but that’s how I am.

For your first point, I think simply proof reading would be your best option – simply read with a conscious, careful eye and things like that should pop out. Have other people read it too.

For your second part, I would suggest drawing out a timeline, and as you go through the book, every time related fact, event, or change should be noted on the timeline. Once it’s been finished, look over the timeline to make sure things move correctly.

get another reader. You are too close.

I write in spurts. I’ll write a pagge one day and a week later write a chapter then a month later write some more. Because of this, I keep a notebook with information about my characters next to my computer and check it often as I write.

You need an editor.

You can do a lot yourself by making a timeline, by keeping character sketches and updating them as you go along, by searching on names and keywords, etc. Eighty pages aren’t enough to really lose track of things. It can get a bit dicey over three hundred.

But the main thing is to have a competent, objective reader who also knows what to watch for and takes good notes run a read-through check for you. This does not have to be a person who loves you. It’s better if it’s a person who reads well, regardless of personal ties.

In other words: I agree in principle with the posts above.

However, as a professional editor myself I would advise you to get well beyond the rough first draft before you start calling on people for that kind of help. You should do everything you think needs to be done first. Don’t worry, once people have read it and given you fair, honest feedback, you’ll find more. But while you can still see need for improvement, do the improving yourself and don’t ask others (whether family and friends or paid professionals) to do the writer’s job for you.