Rules, rules, rules. It seems there’s a lot of them around at the moment.

Where do we have to wear a mask? What countries can we travel to? And how many tests do we need to take when we get there?

You may be one of those people who hates being told what to do. Or you may be someone who finds rules reassuring.

Whatever your view, there’s an undeniable truth about rules: they give you a sound basis for working from when you’re trying something new.

Like writing a book for your business.

In fact, as ghostwriters we’re often asked what rules there are for writing a book. What we say is, if you follow the rules you can’t go far wrong. But – and this is a big one – there’s no need to let them dictate your every step.

Because, just sometimes, rules are made to be broken. The trick is in knowing when.

So, what are the three main rules for writing a business book or self-help guide?

1. Your book’s length should be right for its purpose

Book length is one of the main areas that new authors feel unsure about. Which isn’t surprising given that publishers talk about length in terms of words, whereas most people think in terms of pages.

And how many words (or pages) should you write in any case?

The rules about book length stem from the fact that there are a number of long-held conventions about it. When we hold a book in our hands we make assumptions about what kind of book it is from how thick it feels – is it an in depth exploration of a topic, or a quick and handy guide?

To keep a complicated explanation short, full length business books are normally around 50,000 words (or 200-250 printed pages). E-books and how-to guides can sometimes be shorter.

The size of your topic is also relevant. If you want to write about a relatively narrow subject, such as social media advertising, your book can be short and designed as a reference guide for busy people. On the other hand, if you’re expounding on a theme that demands more detail and expanse, such as the environmental damage caused by the food industry, your book should be longer.

When to break the rules on length

Your book should be long as it needs to be. There’s no point padding out what could be a concise and punchy guide just for the sake of making it more wordy.

Equally, if you have a huge amount to pack in, your book should expand to fit.

If there’s a business book you admire why not count the pages, tot up the words on an average page, and see how long it is in total? That will give you a guide.

2: Your book needs the right structure

The way you structure and outline your book should be guided by both what kind of book it is and what you want your readers to take away from it. If a book doesn’t work, it’s almost always because the structure isn’t right.

The way I see it, there are three main categories of business or personal development book:

• Self-help or how-to guide.
• Transformational memoir.
• Thought-leading, inspirational book.

Think about what experience you want your readers to have. Your outline should be connected to the purpose of your book. What do you want your readers to think, feel, and do by the end of it, and which of these is most important?

If you want them to do something, a how-to guide might be best.

If you’re keen for them to think something, an inspirational book would work well.

And if you’re prompting them to feel something, a memoir or story-based approach could be the answer.

Still stuck? Turn to your bookcase or e-reader and glance through the books you’ve read recently. Which were most helpful and enjoyable for you? Take a look at how they’re structured and you’ll find clues to the kind of book you want to write.

You can also think of your readers. What kind of book would they appreciate? Which outline would suit them best? This is a starting place for you to create your outline, but you need to tailor it to your (and your readers’) needs.

When to break the rules on book structure

You’ll notice the three outline types can overlap.

Your how-to guide might contain some of your personal story, your thought-leading book could include some how-to elements, and your memoir might be partly a self-help book.

So don’t feel you have to be rigid with your outline type, just consider what the main thrust of your book will be and use these formats as a guide.

3. Your book demands a reader-friendly writing style

Most business books and self-help guides are written in a direct style with accessible language. They also address their readers as ‘you’, rather than talking theoretically in general terms.

Here’s an example of what I mean. An academic or theoretical style would be: ‘It’s possible for this to be completed by you or your manager.’ A direct style would be: ‘Either you or your manager can finish this.’

The first is distancing, using the passive voice and longer words than necessary. The second brings your reader close to you by using the active voice and less formal vocabulary.

This is one rule we would heartily endorse. You can play fast and loose with the rules of length and structure if you want, but if you want your readers to engage with your ideas you must speak to them as individual human beings, rather than an amorphous crowd.

You want your readers to be nodding along with you, ready to absorb what you say and willing to take action.

To sum up …

It’s easy to assume that there are lots of rules for writing a successful book.

But really they boil down to three: having the right length, the right structure, and the right style.

And remember that the only REAL rule you need to follow is to remember that your job as an author is to inspire, inform, and entertain. If you achieve that, you can break as many others as you like.