Please welcome Christine Rains, author of 1302 - The Alpha!
Series of books are incredibly popular, especially in the paranormal romance genre. Readers just don't want one anymore. It's hard enough to just write one book, but three? Five? A dozen? If you're in it for the long haul, there are several things to consider.
Should you use one protagonist throughout the series or have several? My 13th Floor series has six books, and each story is told by a different narrator. I like that it allows the world to feel new to me again, and I see different aspects of it through the characters' eyes. Yet having one protagonist can also work. Take Harry Dresden or James Bond for example. Two amazingly popular characters. The series have the same characters in new adventures. Lovable and reliable.
Must the books be read in order or can a reader pick up any book in the series and feel they're not missing out on anything? Most series are meant to be read in a specific order. Sometimes this frustrates new readers. Some books have stories that stand alone but drape it with one larger plot that stretches through the series. Whichever way you choose, make it clear to your readers.
How much of the worldbuilding should you repeat in each book? Tricky question. You don't want to bore previous readers, but you want to write enough to refresh their memory and not leave new readers clueless. Make sure your readers know your protagonist's motivation, what major event(s) happened previously, and the rules of your world. The rest can be shown as the story develops.
Writing a series is going to take years. You must be prepared to make the commitment. Be certain you really love these characters and that world. Take notes. Lots and lots of notes. And keep them organized. Don't follow my lead in keeping a notebook with random notes throughout!
Good luck and happy writing.
Thank you Christine!