Gretchen Rubin, author of the bestselling books, “The Happiness Project” and “Happier at Home,” calls herself a street scientist: she’s fascinated not just by human nature, but how we as humans can change. In her new book, “Better than Before: Mastering the Habits of Our Everyday Lives “ Rubin puts our habits under her microscope.

Want to develop better habits? Figure out your habit tendency, she says. Are you, like Rubin, an “Upholder,” who can meet internal and external expectations? Or are you a  “Questioner,” like Jane Eyre, who’ll only do something if they think it’s justified? An “Obliger,” like Andre Agassi, who is motivated to meet the expectations of others? Or a “Rebel,” who resists both internal and external expectations? Different tendencies require different strategies for change. Obligers respond well to accountability partners. Rebels don’t. Rubin explains:

Q: How did you go from happiness to habits?

Rubin: I was obsessively talking to people about their happiness and researching it and writing about it. And I really began to notice this pattern that a lot of times when people talked about either a big boost that they’d gotten in their happiness, or a big challenge they were facing, that really, at its core, it was a behavior that had something to do with a habit.

People would say ‘Oh, I’m exhausted all the time.’ Well, really, that’s about the habit of getting enough sleep. So I became more and more interested in the role habit formation plays. Research says habits make up 40 percent of everyday life, so they really are the invisible architecture of our lives. I you have habits that work for you, you’re more likely to have a happier, healthier and more productive life. And if you have habits that don’t work for you, it’s going to be a bigger challenge.

In a way, this book is almost like a prequel to the Happiness Project – about how are you going to build in those habits that are going to make you happier.

Q: How do you recommend starting to change a habit?

Rubin: Begin with yourself. Forget what Steve Jobs did, or Albert Einstein, or Gertrude Stein. You have to think about what’s true for you. What have you succeeded in in the past? What are your circumstances? You’re never going to escape yourself. So you have to form the habits that are suited to you. And when you do, that’s when you can change.

Q: What about you? Had you worked on your own habits before The Happiness Project, did it come as a prequel, or later, as a sequel?

Rubin: It’s interesting, something very, very challenging happened during the writing of the book. When you study happiness, there are all these scales – on a one to ten, I was a seven – and I had all these ways of evaluating myself in comparison to other people. But with habits, that doesn’t exist. I launched into this book about writing about habits, and I thought I was pretty typical. If I’d thought about it, I probably wasn’t that typical, because people would always come to me and say, ‘You’ve done all these things, how do you manage to stick to them? How do you get yourself to write a blog everyday for eight years, six days a week?’ And I’d say, ‘Well, it’s not that hard. I just made up my mind to do it.’

But what I discovered in writing my book, and developing my Four Tendencies Framework is that I actually have a very extreme type of personality. And there are a very small number of people like me. For someone like me, an Upholder, I have to say, habits come pretty easily. I didn’t understand how many people didn’t have that same experience. So, before The Happiness Project, I had worked on my habits. But I’d already had really good habits stretching back pretty far.

 Q: What were some of the early habits you developed that have made a difference for you?

Rubin: I never missed deadlines. In college. I never pulled an all-nighter. I’ve exercised regularly since high school, even though I’m a tremendous couch potato. I’ve always been good about getting enough sleep more or less. And then one of probably the most dramatic habits changes I made three years ago, before I started working on the book, which is the habit to eat a very low carb diet. And that was huge, because I used to have to use a lot of management around craving control, because I love sweets, I love breakfast cereal, oatmeal. I love all that food. But when I read Gary Taube’s book, ‘Why We Get Fat,’ overnight, I changed the whole way I eat. It’s much easier. I’m much less hungry. I don’t have cravings. (Rubin nibbled on a high protein Slim Jim as we spoke)

I wasn’t a person coming from a place of a lot of bad habits – which would make me more typical.

Q: So you don’t have any bad habits?

Rubin: I’m a real hair twister. I don’t write about nervous habits. But I don’t try not to do it anymore. I’ve made my peace with it!

Q: OK! What surprised you the more you looked at habits?

Rubin: One thing that really surprised me – it was so counter intuitive that it took me a long time to understand it. Finish lines are very undermining for habits. Because a lot of times people will set a finish line thinking they’re forming a habit. They’ll say, ‘I want to get back into exercise.’ Then they’ll train for a marathon. Or they’ll do a 30-day yoga challenge. Or they’ll give up sugar for Lent. Then once they hit that goal, they’re right back where they started.

I thought hitting a goal would energize you, and make you more committed to your habit. But in fact, it’s just the opposite. I realized, it’s a finish line. When you finish, you feel you’re done. Which means, if you want to keep going, you have to start over. And starting over is hard. So it disrupts a habit.

Q: So what do you suggest people do?

Rubin: Think about it this way:

*It’s a Milestone, not a finish line. If you want to exercise indefinitely for the rest of your life, think about running a marathon, or whatever, as an exciting milestone, not a stopping point.

*Have a Plan for how you’re going to continue to continue your habit after you reach your milestone.

*Create Safeguards. What are you going to do when you’re on vacation, if you’re sick, or it’s your birthday? Or your schedule changes. Have a plan for when things change.

*Plan to fail.

Q: Failure can be so discouraging for people. How do you tell people to address it?

Rubin: When you’re thinking about forming habits, you have to have two exactly opposite ideas in mind at all times:

*When you’re starting a new habit, you don’t want to slip up. The more you stick to that habit, especially at the beginning, the harder and faster that habit clicks in. So you really, really want to be consistent, and use the strategy of Safeguards to avoid pitfalls and Loophole Spotting to spot those loopholes you’re likely to invoke so you can ward them off.

*At the same time, you want to keep the completely contrary idea in your head, which is, ‘It’s OK to slip up. It’s not a big deal.’ Sometimes people think if they load themselves with guilt and shame they’re more likely to stick to a habit. But research shows that people who show compassion toward themselves are much more likely to get back in the saddle.

You can fail big or fail small. So you want to Fail Small. Plan for it. Keep it limited. Forgive yourself. Learn from it. And don’t think it means you’re done.

The author of "The Happiness Project" talks with The Post's Lillian Cunningham about how the most creative, productive people structure their time. (Lillian Cunningham, Jayne Orenstein, Kyle Barss and Julio Negron/The Washington Post)

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