Yet, when the machine finally started working again, I made a fantastic discovery.

That little icon at the bottom of my screen that flashed as each new email arrived was no longer there. And, not only did I survive the day quite happily, I realized I was much more productive.

It helped me recognize the importance of taking control of my time. As business owners, time is arguably our most precious resource. We can choose to sell it, invest it or waste it. So the more effectively we use it, the greater our chances of success.

Here are my 7 tips for mastering time.

1. Know how much your time is worth - The first step in getting control over your time is knowing its real value. The most obvious way to value your time is just to divide your annual earnings figure by the number of hours you work in a year.

But our number of productive hours is much lower than the actual hours we work. So to get a better picture of the real value of your time, estimate your number of productive hours ? for most people it's less than three a day.

Once you know your hourly value, you should ask yourself if what you are doing is worth your hourly rate. Outsourcing activities is now so easy that you can often pay someone else significantly less to carry out tasks.

2. Clone yourself (or your work) - While it's not yet possible to clone yourself, you can easily clone your own work without any ethical issues. When you've written something, leverage it for maximum benefit. With a little additional work, a presentation script easily becomes a magazine article or a sales letter, for example.

3. Spend more time on output than input - Are you spending too much of your time reading emails and learning new things? When you're inputting information, you're not outputting. And it's only output (like working for clients and developing products) that makes money. New knowledge and different ideas are valuable but sometimes us info junkies need to go on an info diet!

4. Decide what work you are willing to leave undone - No matter how efficient you are, you can't do everything you'd like to. If you're busy, one of the most useful things you can do is to transfer some unnecessary tasks from your "to-do" list onto a "not-to-do" list ? then quickly forget about them.

5. Manage your day with time limits - When I stopped reacting to that flashing notice of every new email arriving, I set aside specific times each day for reading emails. I now limit the time for doing that and scan them quickly using a "one-touch" approach where I immediately act on the email or delete it.

Another technique that works well is to use a timer to help you focus on work for fixed periods. Some people work well in short bursts completing specific 15-minute tasks before moving on to the next one. For other people ? and other tasks ? longer time limits of 45 or 60 minutes work better. But you need to be disciplined and stick to the limits.

6. Focus on your priorities - Decide which one, two or three big tasks you need to complete today or this week. Then concentrate on them before doing anything else.

7. Develop systems and processes - If you have your work organized into clear processes, you can more easily manage your time. While it makes tasks much easier to delegate, it's also a better way of using your own time more efficiently.

The more you control your time, the more profitable your business will be.