If you’re self-publishing for income, you’ve probably heard that you want to write in series. More books gives readers something to look forward to and a better backlist if they want to read while they wait for your next release. It’s also easier to work with established characters and scenarios instead of creating a new universe every time you sit down to plot something out.

But just knowing to write in a series isn’t enough. How long should your series be? Should you plan it out beforehand or can you make it up as you go?

Here are five secrets about writing a series for profit that will help you steer yourself in the right direction.

Secret 1: Sometimes monster-of-the-week is best.

It’s tempting to plan a sprawling epic. Often an idea will build and build until it fills a series, and Saturday morning monster-of-the-week feels flimsy by comparison. But with the lighter structure comes less responsibility.

You don’t know which of your ideas will fly, starting out, and if you commit to a ten-book multi-generational space saga, you might find yourself having to decide between abandoning it altogether or writing something that you discover too late will never sell.

With an episodic structure, you can make a series as long or as short as you want. If you come up with a better idea or if the series stops selling, you can easily quit it to move onto a future project.

Secret 2: If it bombs, drop it.

Let’s say you publish the first book in a series. This might be a series that you’ve planned well in advance, or you might be winging it. Either way, it doesn’t sell. At least, not as well as you’d hoped.

Everyone has trouble getting started, and a flop for a first or second book is extremely common. But you don’t want to keep writing in a series that has no audience.

When you’re writing a series, keep in mind that the market will come and go. Some months will bring clusters of new readers to your books, and some months, your audience will dry up. Don’t cling to a project so tightly that you can’t leave it if needed.

Secret 3: Prepare to be flexible.

You won’t go far if you commit yourself too firmly. A rigid and unchangeable publishing schedule or a commitment to a work in progress might not be practical in the end.

Your editor or cover designer might go on vacation. You might have a family emergency. The series you’ve been pounding out might dry up entirely on the sales front, or your preferred sales venue might have an algorithm change that alters everything.

Flexibility is key to being able to make it. You need to adapt to the time and cultivate a fluidity that you can apply to every book you put out.

Secret 4: Promote the sequel.

A popular conundrum that comes with writing a series is what book to promote. The obvious answer is to promote the first book so that it can get more readers. After all, you don’t want people to jump in on book three unless the series is non-sequential.

But if we’re talking about advertising on Amazon or your current following, the rules are slightly different. Plenty of people who read your first book might still be waiting for your next book, and if they liked the first they’ll happily buy it.

The trick is to know your advertising platform and whether prospective readers are more likely to see the ad or if established readers will stumble upon it instead.

Key tip: Amazon tracks who buys your books. If you advertise a later book in the series, Amazon will promote that book to people who have already read or bought the earlier ones. This could be much more profitable than promoting your first book repeatedly to people who aren’t interested.

Secret 5: The later you are in a series, the less you need to worry about production.

This is a down and dirty trick. Ideally, it shouldn’t matter. If your series is lucrative, it should more than pay for itself, and production should be simple to afford.

Here’s the deal: Once your readers are sold on your series, they’ll want to keep buying. It might take a few books to hook someone initially, but if you need to make an adjustment several books down the line, your readers will most likely be forgiving.

I’m not recommending that you cut quality. Again, later books in a series should pay for themselves, and if you’re successful, you shouldn’t need to cut back. But it’s good to know when it’s okay to be flexible.

What has your success been when writing a series? Please share your best tips in the comments below, or click on the blue button to join my Facebook group for self-publishing fiction writers.