While in the midst of writing “Angel,” I discovered that this could not be a single book. Angel’s story had to consist of several books.
Writing a book series can be sometimes more overwhelming than writing a single book. Some may say it’s nothing more than breaking a long book into multiple shorter books. But series are much more than that.
One aspect of a series is how the characters grow. Anybody who grew up with Harry Potter knows this. Harry started out as an eleven-year-old, with all of the mannerisms of an eleven-year-old. However, Harry grew up. His character developed, along with the other characters in the book. Other authors should remember this. Think about how events change one’s outlook.
For example, if a character witnessed a violent crime and had previously never been exposed to something like that, they would probably have a different outlook on life. This one even could change them completely.
Another aspect of writing a series to remember is continuity. If your character was terrified of spiders in the first book, make sure your character (unless faced with an experience that demanded the change) is still afraid of spiders in the 5th, 7th, 11th, and 15th book.
Use your other books as references. You just spent a long time writing a book- of course there will be details you don’t remember.
Decide if you’re continuing adventures of a certain character (similar to Nancy Drew or Robert Langdon-The Da Vinci Code) or if you’re continuing a specific adventure (similar to Harry Potter.) Once this has been decided make sure you don’t get too repetitive or wearisome.
Above all: KISS- Keep It Simple, Stupid. If the story becomes too difficult to write, it will become too difficult for readers to follow. Sometime’s it’s necessary to cut out huge chunks in books; Everybody does it!