Of all the keys to writing a successful book series, one stands above and beyond all the rest. It’s not what the author usually wants to hear, but it’s the cardinal rule for series writing. You must plan out the entire series before you start writing. In this way, you can avoid some of the most common errors that plague series writers:
• Killing off characters prematurely. You do not want to put yourself in the position where you’re saying to yourself “Oh, phooey. This would be a perfect spot for Julius to walk in, but I killed him in the first book.”
• Not killing off or making characters disappear soon enough. Sometimes the reader just gets sick of the vengeful neighbor, the annoying aunt, or the precocious kid. Pick your spot and send him or her to their destiny.
• Having a great first book, but then a lull in the second. If the reader is disappointed at any stage, they are less likely to stay engaged throughout the series. By planning the entire series, you’re more likely to avoid this pitfall.
Successful series always feature an appealing lead character. Think Sherlock Holmes and Harry Potter. They are so appealing, so compelling, that they themselves are almost enough to guarantee that the series is successful.
Another good idea is to read a series or two before you attempt to write one. Remember, you’re not writing a serial, you’re writing a series. Each book has to stand on its own. You want to be able to grow your audience. Requiring potential new readers to read books one, two and three in order to understand the just-released book four is a major impediment to building an audience. On the other hand, if they like book four, they are very likely to want to read what came before.
In movies, there’s a thing called continuity. It means that as multiple takes of scenes are shot, the actors must have the same wardrobe, the settings must look identical, everything must be consistent when the various takes are put together in the editing room. Similarly, when writing a series of books, there’s the need for consistency. If a character mentions his rheumatoid arthritis as a reason for not getting up in the morning, it won’t do to have him rock climbing later on in the series. This is true for stand-alone books too, but for a series it can be particularly tricky because there is so much more content, and so much time that elapses between the start and the finish of the series.
So set yourself up for success. Plan out the entire series, at least at a high level, before beginning book one.