Books about habit forming usually refer to well-worn examples of incremental improvement and compound interest. 'Improve by 1% a day, and in just one year you will be a 3678% samurai ninja hunky millionaire!' 

There is no denying the power of accumulated marginal gains.

Increase your daily run by a minute per day, and you'll soon be running for miles. Save £20 a week, and you'll be able to afford a £1000 adventure in a year. If you have a good idea, write a short blog post every day. You'll eventually have written a book. 

But it can be hard to remain inspired by a distant goal when you contemplate the number of tiny, tedious sacrifices required before you reach that point. It is helpful then to decide to do a specific thing today, just once. Do it. Tick it off on a piece of paper. Done. Nice and easy. The day after that? Do it again. Tick it off. Done. 

Deciding to eat healthily today is far more fruitful than a pie in the sky plan (or a no pie plan) to 'lose three stone'. It is the difference between discipline and a mere tweak of your habits. Our idealism is greater than our willpower. A small, specific daily deed is more achievable than vague goals with wiggle room and get out clauses. Eat a carrot, not a carrot cake. Get up tomorrow and repeat. 

I have used a habit calendar to cajole my lazy ass into 100 consecutive days of doing 50 pull-ups and 100 days of meditating. I'd never have kept those up without the chart. 

A habit calendar makes things easier, but it does not make it easy. My 'Write this Damned Book' calendar, for example, keeps failing. But every time I fail, I start again, doing my best to string together a longer sequence of X's than I managed last time.

Once you build up a streak of daily successes, you'll not only find each one easier, but you will also become increasingly reluctant to break the chain. I like the notion of 'no more zero days': do one tiny thing every day to keep creeping forward. Build your habits, and the big goals will follow along behind them. Our hours become our days. And one day we will stop, look back and realise that those hours became our life.