If you're a new author with one or two books, then it can make sense to go exclusive with KDP Select, because you're building your backlist and getting to grips with everything that goes into being an indie. (More on the pros and cons of exclusivity here).

But authors who are serious about building a long term career with their books, who want to sell on all platforms, to all markets, mostly choose to take their books wide.

I make an increasing percentage of my author income from Kobo and iBooks, and of that money, an increasing amount is from non-US sales.

And some authors even make more money from iBooks than they do from Amazon, for example, Liliana Hart, interviewed here.

You can publish direct on iBooks if you're a Mac user, or you can take advantage of all the same opportunities by publishing through Draft2Digital or Smashwords.

So if you're ready to go wide, or if you want to expand your sales, here's how to sell more books on iBooks.

(1) Write in a series and use a permafree series starter

iBooks has specific promotions for free first in series and iBooks readers are used to using them as a way into a new author's books.

iBooks readers are also less price sensitive because there is no subscription model, so even if you give the first away as a free starter, you can still put the rest at full price.

There's also no $9.99 cap on royalties so you can sell higher priced boxsets. Again, iBooks readers are used to these as they're offered by traditional publishing at pretty high prices e.g. George RR Martin 5 book boxset at $34.99.

When publishing, you can use a series field to link all the books together, so make sure you spell your series name and author name consistently to take advantage of that. If you publish direct to iBooks, you also get more choices for categories which can aid discoverability.

(2) Use pre-orders and promote them to your readers

You can add ‘asset-less' pre-orders on iBooks up to a year in advance, which means you don't need a cover or a sample or even too much of a description. Having it there for so long means that as soon as someone finishes a book, they can order the next one with no need to remember buying it later.

Obviously, you should aim to meet your pre-order date but there's no penalty for changing the date if you need more time, or even if you deliver it early.

Pre-orders on iBooks also rank twice.

They're counted in the iBooks bestseller lists while on pre-order and then you get the sales counted all on the live date. Awesome!

As someone who has only just started to get serious about pre-orders, I can tell you that it does make a difference over time. Yes, you have to be more militant about planning in advance, but it helps to keep to the production schedule and customers know what to expect next. My next book, Destroyer of Worlds, is currently on pre-order at iBooks and I'll have the next book in the series up by the time it goes live on 21 April 2016.

(3) Do a cover reveal and early sample while the book is on pre-order

You can drive customers to the pre-order by revealing aspects during the journey to publication.

Start with just a title and no cover a year in advance, then do a cover reveal a few months out and then use an early sample of first two chapters. This gives you three chances to promote the pre-order, plus if it's a series, it will be linked on the iBooks page.

(4) Link directly to the iBooks store as you promote your books

Some authors complain that they don't sell any books on iBooks, but when I look at their website and social media presence, there's no evidence of them actually promoting their books there.

Add iBooks links and buttons to individual book pages so visitors to your website will click through to buy. (For specific examples, check out How to Make a Living with Your Writing, and Stone of Fire).

You can also share directly from iBooks to social media. The link to Twitter shown on the image right produced the tweet shown left, and people can click directly through to purchase.

(5) Use promo codes for reviewers

You can get promo codes that enable you to give your books away for free to reviewers or people on your mailing list.

This helps give your book social proof and iBooks, like all stores, has algorithms that help discovery for books with more reviews and more ‘traffic.' Everything helps!

(6) Think mobile for marketing

iBooks is now the default reading app on all Apple devices. There are also in-app purchases, unlike Amazon's Kindle app, which makes it easier to buy with a click.

Share direct links to the iBooks store when you tweet or update a Facebook status and readers who are browsing on mobile will be able to click and buy immediately.

iBooks is also keen on image marketing so make sure you include great images in your marketing. Don't be tied to just your cover. Think about the themes, people, places and quotes that might arouse interest in your book and use those in your advertising.

(7) Optimize your chances for discovery by merchandising

iBooks merchandising is done by team members all over the world who love books and actively look for authors and books to feature for promotions. You're more likely to be noticed if:

• You have a number of well-written books with great looking covers and social proof through reviews.

• You utilize the best practices as above and demonstrate that you're actively promoting your books on iBooks.

• You avoid bouncing in and out of iBooks as you choose to go in and out of KDP Select. Every time you pull your books, you damage your velocity at the other stores.

• You seek out iBooks reps at author events and develop relationships over time by demonstrating you are focusing on iBooks.

You can find more on marketing your books on iBooks here.

Do you have any tips for selling more books on iBooks? Please leave a comment below and join the conversation.