When your writing remember to make up your mind!

I found an old book called Inside the Talking Cake. No it has nothing to do with the making of that stupid book, it was supposed to be about my sister and I are transported into the book and find out that we caused some of the major events. Now I'm all against the idea of a real person being in a fiction novel.
I did noticed that the main plot line was being changed constantly. In one chapter the organiser controlled the book, but in the other chapters the author controlled the book. It was highly confusing and I even noted in the book, "Wait do the witches want me or the organiser?". It became soo confusing that I actually had to say something about it in the book. My advice is when you are writing any novel to have your plan in mind and not constantly changing details without going back and seeing if it makes sense. I was constantly changing the plot and major details that the book fell apart. That is a book that I never plan to remake.
-AM