What is a habit? Bestselling author Gretchen Rubin explains that habits are “like the invisible architecture of everyday life,” decisions that we’ve already made. Unfortunately there is no simple, one-size-fits-all solution for replacing bad habits with better ones. Rubin walks through some key points from her new book Better Than Before: Mastering the Habits of Our Everyday Lives.

Gretchen Rubin: So what is a habit? I think the key thing about a habit really comes down to decision-making because sometimes people think about it’s something that you do repeatedly, you know, it unfolds over time. But really the key thing about a habit is that you’re not making a decision. You’re not deciding whether to brush your teeth. You’re not deciding whether to use a seatbelt. You’re not deciding whether to go to the gym first thing in the morning. You’ve already decided. And the advantage of a habit is that once something’s on automatic pilot, then the brain doesn’t have to use any energy or willpower to make a decision. You’ve already made that decision. You’re just moving forward. And so it happens easily without any thought, without any willpower, without any effort. You’re just on cruise control and then you can do what you want to get done.

Habit is like the invisible architecture of everyday life. Research shows that something like 40 percent of what we do every day we do in pretty much the same way and in the same context. So it’s easy to see that if you have habits that work for you, you’re much more likely to be happier, healthy and more productive. If you have habits that don’t work for you, it’s really going to drag you down because such a big part of our day is taken up by habits.

One of the mysteries of habits is why do we persist in having bad habits when we know they’re not good for us, when we know they don’t make us happy. But, you know, there’s usually multiple things going. Maybe it’s what you want right this minute versus what you want on the long term. Or maybe you want two things that are in conflict. On the one hand you want to have plenty of time to hang out and goof around. On the other hand you want to have a clean, pleasant apartment. So you have two things that are in conflict. So when you have a bad habit, it’s very helpful to think very clearly, "What do I really want over the long term? What’s really most important to me?" And that can help you fight back against the pull, that gravitational pull that a bad habit can exert.

One of the things people say about habits sometimes is they’re like, "Make healthy choices." And I completely disagree. Don’t make healthy choices. Make one healthy choice and then no more deciding. The reason that habits can give us so much more power in our lives is that they eliminate the need for decision-making. You could just decide one time what you’re going to do and then you don’t revisit that decision because every time we make a decision, we have the opportunity to decide wrong. And even if we decide correctly, we still are using a lot of energy to battle with that decision. So you really want to use decision-making to set out a habit that you want and maybe to anticipate a lot of the challenges, a lot of the stumbling blocks that you might encounter along the way as you’re trying to form that habit. But once you’ve made that decision, don’t look back. Decide once and then no more deciding.

One question is whether you’re better off trying to do one habit at a time if you’re trying to make change or whether you do many all at once. And like many things of habit formation, there’s just no magic answer. There’s no one-size-fits-all solution. Some people do better when they start small, when they keep it very simple and they gain the habit of the habit. They get a feeling of accomplishment and it’s very manageable and realistic because it’s something very small. It’s just like one thing. But on the other hand there are some people who love to go big, that love big transformation, big challenges. And so something to do is to think about yourself and think, "Well what have I succeeded in the past?" or, "What appeals more to my nature?" and to think about what works for you because there really isn’t one perfect way to change a habit or to change a bunch of habits. It really depends on what’s going to work for you.