I know of a guy who wrote a Letter to the Editor. His writing was so good that he was offered a position with the newspaper writing his own column.
He started out writing a letter and found himself doing something much more than what he originally intended.
I relate to that guy.
I started out to write “stand-alone” books.
However, readers liked my characters. They wanted to read more. I was soon hoodwinked into writing a second book—and now a third.
I’m not complaining, though. I’m glad people want to read more about Marcus, Simon, and the others.
An author has choices when writing a series.
First choice: build successive books on the previous ones and simply continue the story. In this case, the reader would need to read from Book 1 through the entire series for the progressive story to be understandable.
Second choice: continue with the original characters in Book 1, but be careful to use epilogues and/or prologues—and effective beginning chapters—to make sure important information from previous book(s) is passed along throughout the series. Essentially, books like these can be read as stand-alones.
Each book can be devoted to a different character, keeping them in the same setting (Ex. On the farm).
Or, each book in the series can focus on the same main character, but in different settings. (Think Gulliver’s Travels).
Or, change the characters, but keep the ongoing theme. (Stories about near-death experiences or angel sightings…)
The possibilities are probably endless. You just have to find that common thread and begin to weave it throughout your series.
In the series I am writing, currently, each book is based on a childhood game, thus the titles Simon Says, Truth or Dare, Tug of War, and so on.
The commonality isn’t just found in the games, but—more importantly—in the way they make their life choices, the result of those choices, and how each one affects their future.
Surveys tell us that readers latch onto a series or a particular author and will follow them until they become tired or disappointed.
So, writing a series can be an effective way for an author to gain a following—and keep them following—if you give each book your very best effort.
Then—and only then—will they keep coming back for more.