Matt Cutts, an engineer at Google, has but one simple challenge for you: to make a difference in your life, pick a small change and stick to it for 30 days. Turns out, those 30 days are just the right amount of time to add or subtract a new habit – whether it be no more soda or a 20-minute jog each day.

30 days will pass whether you like it or not, so what will you try?