Midnight on New Year's Eve is the traditional time to make great resolutions: 'I really mustn't drink as much as I did last year,' or 'This year I am going to start exercising.' But in the cold hard light of New Year's day, it is easy to decide that the promises we made to ourselves are just too hard to keep.

When we fail to live up to these goals, we walk away a bit damaged. The experience of not carrying through a personal goal chips away at our self-esteem and makes us feel less successful. But the difference between good intentions and failed intentions comes down to one thing: knowing that self-change is one of the hardest things we will ever do.

If you're making a resolution, then it pays to do a bit of planning and give yourself a better chance of succeeding. If your resolution is to start running every morning then give yourself a hand: the night before your run, lay out those running clothes beside your bed.

It will be easier to get yourself into the routine of getting ready and getting yourself out the door. Strategies like these are called 'implementation intentions' and they help you get the good habits started.

It's also a good idea to get used to new habits at a gentle pace. If you want to stop smoking and you're a "pack-a-day" person, then don't go the whole hog and give up entirely overnight. Part of you will still want that cigarette, so wean yourself off them gradually. Start by cutting down and give yourself realistic goals to achieve every week.

One more thing to remember is that everybody slips up sometimes. There will come a day when your resolution slips and you find yourself sliding back into those old bad habits. Don't take this as an opportunity to give up completely, tell yourself that tomorrow will be better. It always is.