“Think about something you’ve always wanted to do and try it for the next 30 days”
This is Matt Cutt’s suggestion in his inspiring 3 minute TED talk.
He says that using this method to do things like cut caffeine, cycle to work, cut sugar and take a photo each day led him to enjoy life  and be far more adventurous. This resulted in him climbing Mount Kilimanjaro which he says he never would have done before. Judging by the pictures of him before he started this habit, he also looks a lot fitter!
One of his final nuggets of wisdom was that:
“I learned that when I made small, sustainable changes, things that I could keep doing; they were more likely to stick”
Matt Cutts TED Talk