6 Tips From Successful CEOs for Getting More DoneThe main thing is to have a system for the stuff you deal with the most and can't delegate.

What do successful CEOs and entrepreneurs do about time management, leadership and work/life balance?

Whether they hail from Silicon Valley, the Fortune 500 or are startup founders, the following day-to-day habits all have a common theme: busy leaders credit them as effective secrets to theirsuccess- and as real helps in avoiding or at leastminimizing stress.

Here are some of the top tips from top CEOs:

1. Color-code every minute.

Patrick Gelsinger, CEO of software company VMWare, faithfully codes his schedule by color. He marks meetings blue when they're with partners or customers, red if they're with investors or media, and yellow for strategy sessions. An intern adds up how his time use compares to contemporary studies on executive time management.

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2. Don't work while flying.

Phil Libin, chief executive of the note-taking and archiving software Evernote, says he spells himself by not working while in the air anymore.

"Like everyone else, I used to just work on airplanes. I'd use that as a time to catch up on things," he said during avideo interview. "And I stopped. I basically said when I'm on a plane, I won't work. I'll read, I'll play video games, I'll sleep, I'll watch movies, but I don't work. It makes me look forward to flying. I can get off a long flight, and actually be kind of relaxed."

BestAndroidAppsput together a coollistof apps to use in a plane if you choose not to work there.

3. Have employees put a response deadline in their emails.

Katia Beauchamp, co-founder of the wildly popular subscription beauty-sample service Birchbox, toldLifehackerthat one of her favorite time-saving strategies is to get colleagues to include deadlines for even the simplest of questions.

"I insist people on the Birchbox team indicate when they need a response in all emails," she told Lifehacker. "It makes prioritization so much faster."

Related:5 Bad Email Habits That Waste Your Time

4. Write letters to employees' parents.

PepsiCo CEO Indra Nooyi write letters to the fathers and mothers of all of her direct reports. She most often tells them how pride her mother and family in India were when Nooyi became CEO. She thanks them for their child.

Nooyi said has expanded her letter writing habit to include the top 200 people in the company, as well as some new recruits. That helped her convince at least one to come onboard.

5. Use the 'Yesterbox'.

David Nazaryan, owner one of the nation's top marketing companies,DMG, uses theYesterbox techniqueto navigate the 500-plus emails he receives each day. He deals with email from yesterday today. That way he starts the day knowing exactly how many messages he has to answer and feels a sense of accomplishment when finished.

6. Put notes in your address book.

When Etsy CEO Chad Dickerson puts a new name in his address book he makes a note about where he met that person and what they talked about. If he needs to reach out later he can reference their specific discussion.

Dickerson has a system for everything from how he manages his email accounts to snagging business cards at conventions. He is such a big fan of systematizing entrepreneurial tasks that he teaches a class on it at his company.

"It doesn't matter what your system is, you just have to have a system," he says.

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