Interview: Elisabeth Egan.

I got to know Liz Egan because so many people told me, “You’ve got to meet Liz Egan! ” We knew so many people in common that finally we just had lunch — which was a ton of fun.  She’s the books editor at Glamour and has written for numerous publications, and we have writerly friends in common.

Now she’s also a novelist.  A Window Opens is funny and perceptive novel about a woman who makes a big career change and has to manage that — as well as her family. Think Where’d You Go, Bernadette and Bridget Jones’s Diary.

I was interested to hear what she had to say about happiness, habits, and productivity.

Gretchen: What’s a simple habit that consistently makes you happier?

Liz: I take a bath every night. I get my best thinking done in the tub, and most of my books have wavy pages from getting dripped on by our leaky shower-head. I don’t have any fancy bathing rituals—I use strawberry Suave in lieu of real bubbles. But closing the door and sitting in one place for a half hour is ritual enough. My kids are constantly shouting questions at me over the sound of the water: More ice cream? New sneakers? Permission to watch a movie? When I’m in the tub, the answer is almost always yes.

What’s something you know now about forming healthy habits that you didn’t know when you were 18 years old?

Habits don’t just happen, you have to make a decision about what you want to do and commit to it. For instance, I used to be a serial loser of wallets. Every few months, one would disappear into the ether and I’d begin again. This was back in high school, when you’d collect wallet-sized pictures of your friends in little clear pockets, and the thickness of your wallet indicated your position in the social food chain. I wasn’t so concerned about losing my membership card from the Boris Becker Fan Club or ten dollars of babysitting money, but it killed me to have to collect a whole new batch of pictures. I finally committed to a simple habit: glancing over my shoulder every time I left a room, just to make sure I wasn’t leaving a wallet in my wake. You’d be surprised how often I was! I don’t know why it took me so long to realize that wallet retention requires responsibility; it’s not just a matter of luck.

Which habits are most important to you?

I’m committed to habits that give me the illusion of organization. This is why I write everything down, on real paper with an actual pen. I never leave home without two Moleskine notebooks. The black one is my calendar, which shows one week per two-page spread, with space at the bottom for my weekly to-do list. This is command central for everything from high school orientation to work deadlines to my mother-in-law’s birthday. The yellow notebook contains my daily to-do lists, with Glamour things on the right hand side of the page and personal items and notes on the left. I’d be lost without either one of my Moleskines, but the yellow one is the one I’d be embarrassed for someone else to see, since it contains loony ramblings unfit for public consumption.

Has another person ever had a big influence on your habits?

My husband’s fitness and nutrition habits are a big influence, mostly in aspirational ways. He’s incredibly disciplined about exercise and is naturally inclined to eat an apple when I’m digging into my second piece of apple pie. His habits are so ingrained, they’re actual facts: he’ll always make time to ride his bike or cook a healthy meal. I intend to do these things but inevitably run out of time because I’d rather call my sister.

Have you ever been hit by a lightning bolt, where you changed a major habit very suddenly, as a consequence of reading a book, a conversation with a friend, a milestone birthday, a health scare, etc.?

These questions are my lightning bolt. I’m giving up Diet Coke! I’ve had at least one can every day since I was a teenager and it’s a bad habit—and also an expensive one that screams, “I’m an old lady!” Check in with me at 3 o’clock this afternoon and we’ll see how I fare.

This story first appeared on GretchenRubin.com.