Being successful is largely about gaining control over some aspects of the external world. But it's difficult to do that until you've got control over the internal world of yourself. In life, the strength of your self-discipline very often determines the likelihood of your success. Because of that, self-control is a skill worth developing and it is just another skill that can be practiced and improved upon - like tennis, playing the piano or programming a computer.

You can see evidence of this simply by watching children. Most of them have terrible self-control. They squirm, lose their tempers, and do the wrong thing no matter how much you threaten or reward them not to. A cookie jar and an adult with a turned-back is all it takes to shatter any child's self-discipline.

Here are some simple exercises you can do if you need to build up your own willpower.

1. Drop a small bad habit: I went to the dentist for a check-up a couple of years ago and found I'd developed my first ever cavity. The dentist asked me if I'd been eating anything sweet. The only thing I could think of was the teaspoon of sugar I added to my twice-daily cup of tea. Apparently, doing this coats the teeth in sugar and leads to cavities.

No problem, I simply stopped putting sugar in my tea. At first, it didn't taste as nice, but now I actually prefer it that way.

This is an example of dropping a small bad habit. Other examples include giving up a regular afternoon snack, pressing the snooze button on the alarm clock, or having one too many coffees a day. Giving up something small but significant is great self-discipline practice.

2. Learn something boring but useful: Most people skip learning important skills simply because doing so is boring. Consider skills like grammar, punctuation, financial literacy, technical skills and the like. I'm sure you can think of at least one such skill that you could do with brushing up on.

Go down to the library or bookstore and pick up a book on the topic you choose. Make sure it's something necessary that you have distaste for. Now read that book all the way through within the next week.

3. Do something you know you should every day for a week: We all have things we know we should be doing but aren't. Perhaps for you it's regular exercise, household chores, or getting up earlier. Choose one such activity and set a week where you'll do it for a set amount of time every day. Make a rule with yourself that for every day you miss, you'll add two days to the end of that week.

4. Set yourself an achievable, but difficult goal with a date for reaching it: Build yourself a willpower game around a particular goal. Perhaps it could be giving up smoking, losing a certain amount of weight, or reading a particular number of books. Organized events such as fun-runs are also good.

Make sure it's something that's reachable with a high level of certainty (such as quitting smoking) as long as your will holds. In other words, no external events other than your own self-discipline should be able to have a major impact.

Develop a single-minded focus on achieving that goal by the set date. Don't let yourself pass the day without reaching it.

5. Have a month where you ban yourself from putting anything off: Every day we get tasks, which can be done immediately, but usually, aren't. Good examples are paying the bills, emptying the dishwasher, or starting a college assignment. Put aside a month where you'll refuse to allow yourself to put such things off. As soon as the task becomes known, force yourself just to do it. Don't allow yourself to wait for even five minutes before getting started, and get the task finished as soon as is humanly possible.