One problem with approaching your work purely in terms of "getting more clients," is that it means you will always have to get more clients. If you don’t work, you don’t have billable hours, so you don’t get paid. Time off will always feel like money down the drain. If you’re not careful, you’ll find yourself on a treadmill, unable to get off. Spend too long on the treadmill and you’ll risk burning yourself out.

The solution is to stop thinking like a "freelancer" and start thinking and acting like a creative entrepreneur. This does not mean you need to get VC funding and take on an army of staff. The opportunities created by the internet mean you can carry on as a one-person outfit or micro-business. What it means is that instead of just working for hire, you start creating business assets whose value will increase over time.

If that sounds a bit daunting, consider these four types of asset, that are within the reach of any solo operator:

1. A Brand - create and project a professional and consistent image.

Designer and developer Nick Cernis could operate under his own name, but instead he blogs as Modern Nerd and sells his iPhone apps under the name Spiffing Apps. His websites’ design and copywriting are consistent, memorable, and unmistakeable. And because Spiffing Apps is separate from Nick Cernis, he has the option of selling the business in future, allowing the next owner to inherit the goodwill and reputation associated with the name.

2. Online Properties - build digital real estate that grows in value over time.

David Airey is an independent graphic designer. Since 2006, he has been writing a graphic design blog at DavidAirey.com, and at LogoDesignLove.com. He ploughs thousands of hours a year into his blogs. Hours he could have spent working for clients or hustling for new business. But now he doesn’t have to hustle for business any more. Clients come to his Edinburgh studio from as far afield as Japan and Canada. His blogs have also secured him a book deal with respected imprint Peachpit Press.

3. Permission Assets - build lists of contacts who want to know about your ideas, products, and services.

According to Seth Godin, permission marketing is "the privilege (not the right) of sending anticipated, personal, and relevant messages to people who actually want to get them." A permission asset could be an email list, a blog subscription list, a Facebook group, or a following on Twitter. Every day, Hugh MacLeod sends a cartoon to the folks who subscribe to his email newsletter. They are free to print it themselves or buy a high-quality, limited-edition print from the artist. Enough of them do the latter to make it a very rewarding enterprise for Hugh.

4. Products - turn your knowledge and skills into physical or digital items for sale.

If you can deliver a professional service for clients, you can certainly create your own product range. Doing this successfully means you develop streams of income that increase over time – and it frees you from the treadmill of hourly or daily rates. Photographer and writer Susannah Conway makes a living from her innovative Unravelling e-courses combining photography, community, and personal development. Matthew Inman has freed himself from web design hell by creating the phenomenally popular Oatmeal website as a showcase for his comic strips, which he sells as posters, prints, and in a forthcoming book.

It’s not easy to find time to create these assets – in the short term, it’s easier to justify work on client projects that will put food on the table next month. But for the sake of your long-term health, wealth, and creative fulfilment, you owe it to yourself to make the investment. And it doesn’t have to be a black-and-white choice – think of the Google engineers who spend 20% of their time on personal projects, or David Airey writing his blogs while maintaining a steady flow of client work.

For more insights on running a client-based business, visit 99u.com.

Mark McGuinness is a coach for creative entrepreneurs based at LateralAction.com and the author of Resilience: Facing Down Rejection and Criticism on the Road to Success.