How Richard Branson, Michelle Obama and other highly successful people use calendar hacks to be happier

People who are consistent with using a calendar and to-do list are about three times more likely to be millionaires than those who don't keep a set schedule, socio-economist Randall Bell says.

If you haven't yet started the habit of keeping and marking a calendar, 2018 can be your chance. Many of today's most influential leaders accomplish all they do by using their calendars not only to schedule work events, but also life events. As a result, they maximize work-life balance.

Here is a list of five leaders and executives who have shared their best scheduling tips to stay productive and happy.

At the Obama Foundation Summit in November, former first lady Michelle Obama said people tend to use their work as a distraction from focusing on what they need as individuals.

"I'm very ruthlessly efficient, but I have to be organized about [myself]," Obama said. "I have to be as organized about my life as I am about my work."

One of the things Obama said she has learned as a mother is that "you have to be fiercely organized to get anything done." When it comes to school events for Sasha and Malia, Michelle and Barack made a point to speak with teachers and principals at least a year ahead to make sure they marked each event they needed to attend.

"If I'm not protecting my time, if I'm not learning how to say 'no,' even to the best things, even to the most worthy things — because I need to sleep or I need to eat or I need to take time out to exercise — then I am no good to my children," Obama said.

One of the tricks Obama uses is to book time with her family and for herself before accepting invitations to conferences, speeches, rallies or political events. Instead, she asks herself, "When do I want to hang out with my girlfriends?" "When am I going to exercise?" "When am I going to take a vacation?" "When am I going to breathe?" and "How do I want my life to flow?"

"I have to plan my happiness. That's the thing, we think happiness just happens and it can, but you've got to work in some happiness too," she said.

When it comes to scheduling, Richard Branson is a strong believer of writing long to-do lists that help him prioritize his time. Even as head of Virgin Group and a serial entrepreneur who manages a packed daily routine, Branson is a strong proponent of making time for yourself.

Just as easily as you are inclined to accept or schedule a meeting, Branson said that you should "open your calendar and schedule time just to dream."

In order to do so, Branson recommends penciling in this time to let your mind wander (just like you would schedule a meeting).

"Far too many people get weighed down in doing, and never take the time to think and feel, Branson wrote on his blog.

By scheduling time to think freely — whether it's an hour, a day or even a holiday — "you'll be able to see the bigger picture much easier," he added.

CEO of JPMorgan Asset Management Mary Callahan Erdoes recently told CNBC that "you have to be maniacally focused on owning your calendar, on having the lists of what you need from other people and what other people need from you."

To take this forward-looking approach, Erdoes recommends you look at the short-term and long-term issues that need to be dealt with and make sure that you are able to "stay on top of that religiously."

"Calendar management is the single most important thing, especially as you get busy and have more responsibilities," she said.

For years, LinkedIn CEO Jeff Weiner has found a habit that he says is crucial for him to be efficient at his job: Schedule time every day to do nothing.

Each day's schedule includes 30- to 90-minute blocks of time that allow him to "process what was going on" around him and "just think."

"At first, these buffers felt like indulgences. I could have been using the time to catch up on meetings I had pushed out or said 'no' to," Weiner said in a LinkedIn post. "But over time I realized not only were these breaks important, they were absolutely necessary in order for me to do my job."

But feeling inundated by seemingly endless meetings is exactly why Weiner took up this habit.

"Use that buffer time to think big, catch up on the latest industry news, get out from under that pile of unread emails, or just take a walk," Weiner said. "The buffer is the best investment you can make in yourself and the single most important productivity tool I use."

"Shark Tank" star and Herjavec Group CEO Robert Herjavec speaks with his assistant at least 20 times a day, he told Entrepreneur in 2016, and noted that if an event does not exist on his calendar, then "it's not real."

Herjavec also makes sure to get a head start on his year by booking his calendar well in advance.

"Plan as much as you can a year in advance and stick to it," he said.

Similar to Michelle Obama, when Herjavec's children were younger, he would sit with his assistant and his kids' school counselor to mark down each school holiday and event.

"Because of that, I never missed a swim meet. I never missed a school play. I never missed anything," he said. "I'd fly from L.A. back to Toronto to be with my kids for one day. That's the great thing about having your own business — the freedom to control your schedule and to do with it what you want."

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