How to Choose Your First Habit (and Make It Stick)

Pick a habit you actually want, not one you feel you should do. Start with one, or two that fit together, not a long list. Decide exactly when and where you'll do it, keep the setting the same every day, and make it small enough for a bad day. Expect it to take about two months, often longer.

Start here: the habit should be yours. A 2024 review of 20 studies on how habits form, covering 2,601 people and published in the journal Healthcare, found that habits people chose for themselves tended to be stronger. Habits done in the morning tended to be stronger too.

One small study in that review had 48 people take up a stretching habit. Those who did it in the morning took about 106 days for it to feel automatic. Those who did it in the evening took about 154. It's a small study, and the review warns that more than half of its studies had a high risk of bias. Still, it's a useful hint if your mornings are free.

So ask yourself what you actually want more of. Not what looks good online, not what someone told you to do. Reading, a walk, 20 push-ups, 10 new words in a language you care about. A habit you picked is a habit you have a reason to come back to.

Fewer than you think. A 2015 review in Psychological Bulletin looked at 150 reports on programs that asked people to change their behavior. Programs that asked for 2 to 3 changes had the biggest effect (0.29). Programs that asked for 4 or more did about half as well (0.14), and the drop was steeper for people with low motivation.

One surprise: asking for just one change wasn't the winner either (0.11). So the lesson isn't 'only ever one'. It's 'not a long list'. Start with one habit, or two that fit together, and add more once the first feels normal.

There's a bonus to starting small. A 2014 analysis in the journal Health Psychology, looking across several programs, found that progress on one behavior made progress on another 1.4 to 5 times more likely. Your first habit may help pull the next one along.

'I'll read more' is a wish. 'After dinner, I'll read 10 pages on the couch' is a plan. Psychologists call this an if-then plan: if X happens, then I do Y. A 2006 review of 94 tests, published in Advances in Experimental Social Psychology, found these plans had a medium to large effect on following through (0.65).

A much bigger 2025 update, covering 642 tests in the European Review of Social Psychology, found effects from 0.27 to 0.66. Plans worked best when they were written in real if-then form, when people genuinely wanted the goal, and when they went over the plan a few times.

For exercise, though, the effect is smaller. A 2013 review in Health Psychology Review found 0.31 right after and 0.24 later on. Still worth doing, just not a guarantee.

Habits grow from repeating something in the same situation. In a well-known 2010 study in the European Journal of Social Psychology, 96 volunteers each picked one daily eating, drinking or exercise behavior and did it in the same context every day for 84 days, rating how automatic it felt as they went.

What should the cue be? A 2021 trial in the British Journal of Health Psychology, with 192 people, compared tying a new habit to an existing routine, like 'after I brush my teeth', with doing it at a fixed clock time. Neither won. Both helped build the habit. So pick whichever fits your day.

Just don't make it rigid. In a 2021 study of 2,508 employees in the journal Management Science, paying people only for gym visits inside a fixed 2-hour window led to fewer visits, and a steeper drop afterward, than paying for any visit. Consistency helps. A window so tight that missing it means losing the day doesn't.

Small enough to do on your worst day. On a good day, anything feels doable. The habit most likely to last is the one you can still do when you're tired, busy or just not feeling it. Ten push-ups you actually do count for more than a workout you keep skipping.

And if you miss a day, it isn't over. In the 2010 study, missing one day didn't derail habit formation. A 2021 study of 273 students, in Organizational Behavior and Human Decision Processes, found that a daily goal with 2 'emergency skips' a week led to 4.0 goal days a week, compared with 2.83 for a strict 7 out of 7. A little slack helped people keep going.

Longer than the internet says. In the 2010 study, habits took a median of 66 days to feel automatic, but the range was huge: from 18 to 254 days depending on the person. The 2024 review found medians of 59 to 66 days in the studies that timed it, and averages of 106 to 154 days.

Those numbers have limits. In the 2010 study, only 39 of the 96 people had data that fit the model well, and anything past day 84 was estimated, not observed. In the 2021 trial, only 23% of people reached the researchers' habit threshold during the study. The honest summary: about two months on average, often longer, and no magic day when it's done.

If it still feels like effort in week three, that's normal. It doesn't mean you picked wrong or that you're bad at this. Week three is around day 21, and the median in that study was about three times as long.

Kairo is an iPhone app for building daily habits with your friends, built on the ideas above, though no study has tested Kairo itself. You pick your habit from a list, and each one already comes with its way to prove it: most with a photo taken in the moment, which AI checks before it counts; steps, sleep and runs from Apple Health; screen time from your iPhone.

Your friends see your proof and you see theirs. When you pick a habit, you're placed in a room with people doing it at around the same hour. And if you build a challenge, you can choose 1 to 5 habits a day, though for a first one, the research above favors two or three at most. Kairo is free.