Benjamin Franklin once said that time is like money. Without being managed properly, how do you know where it's going?   

Time management is one of those issues that we all face at work, but (ironically) few of us have the time to address.

For the world's top CEOs, however, time management simply can't be an issue. Whether you're running multiple companies,  raising money for your startup, or managing a high-performing team, how you spend your time means life or death for your company.

So, if you think you're underperforming or simply want to learn from the best, here's how some of the busiest people do more work than you every single day:

Elon Musk breaks his day up into 5-minute 'chunks.'

Few people are as productive as Elon Musk. The SpaceX and Tesla founder reportedly puts in 85-100 hours a week, yet still manages to spend 80% of his time on engineering and design.

While that might seem unbelievable (and more than a little excessive), Musk has a simple time-management hack that lets him get more done each day. Each workday is split up into 5-minute 'chunks'--even lunch--meaning more tasks are scheduled and gotten to in a single day.

According to Peter Bregman, author of Four Seconds: All the Time You Need to Replace Counter-Productive Habits with Ones that Really Work, this works because we're more productive when we work from a strict calendar, rather than a to-do list. Instead, breaking up your day into chunks lets you prioritize and be realistic about what can actually fit in a day.

Richard Branson keeps meetings to 10 minutes or less.

In a blog post, the Virgin Group founder and CEO expressed his hatred for time wasting meetings:

"A lot of time is wasted in meetings. Agendas get forgotten, topics go amiss, and people get distracted. While some circumstances call for workshops and more elaborate presentations, it's very rare that a meeting on a single topic should need to last more than 5-10 minutes."

To make sure meetings stay short, Branson insists they're done standing up, which gives a physical reminder that time is short. For investor Mark Cuban, he takes it a step further and says that he never takes a meeting unless someone is writing a check

Dan Mall does his most important work first thing in the morning.

In a Reddit AMA, behavioral psychologist Dan Ariely explained how the biggest time management mistake most people make is to "spend the two most productive hours of their day on things that don't require high cognitive capacity (like social media). If we could salvage those precious hours, most of us would be much more successful in accomplishing what we truly want."

For SuperBooked CEO Dan Mall, the answer is to block out two hours at the start of every day for his most meaningful work. That means no email, no meetings, and no calls until a big chunk of meaningful work has been done. 

Andy Groves set a hard deadline for the end of his workday.

The former Intel CEO made sure he always left the office by 6:30pm at the latest so he could be home for dinner with his family. As he explains it in his book, High Output Management.

"My day ends when I'm tired and ready to go home... There is always more to be done, more that should be done, always more than can be done."

Not only does Grove make a good point about understanding the limitations of our productivity, but by limiting his hours at work he's forcing himself to get more done.

In their book Scarcity: Why Having Too Little Means So Much, Sendhil Mullainathan and Eldar Shafir found that having less time to work actually forces us into periods of heightened productivity.