How to Split Your Time Effectively Across Multiple Companies Richard Branson said, "You need to learn when to go forward and when to say no, which can be difficult -- especially if you prefer to say yes, like I do."

One of the most exciting things about starting a successful second business is realizing you have the ability to do it all over again. For some entrepreneurs, diversifying their interests and pursuing multiple passions is the dream of a lifetime.

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However, you have to remember that running multiple companies doesn't increase the number of hours in a day. Therefore, productivity optimization becomes even more important when you have several irons spread across several distinct fires. Strategies to that end? Here are several:

Trust your teams -- both (or all) of them.

As crucial as it is to hire talented people you can trust when you are in charge of just one company, that task is exponentially more important as your number of ventures increases. Even entrepreneurs who run one company can't always give their full attention to every aspect, at least not without neglecting their personal relationships and jeopardizing their mental and physical health.

Leaders who run numerous businesses have to rely on the teams they've assembled for some critical component of one of these companies every minute of every day. In this light, delegation is paramount.

Find people you believe in; give them a set of clearly-outlined responsibilities and expectations; and trust them to do what they do best. In certain cases, you may want to consider giving an ownership stake in a specific company to your best and brightest to solidify their involvement.

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That way, there can be an owner on-site to monitor the day-to-day operations, even when your responsibilities take you elsewhere. Essentially, you have to trust the team you've built and allow these people the opportunity to demonstrate their true potential. In fact, a study from the Ken Blanchard Companies suggested that employer trust leads to improvements in employees' performance and loyalty to the organization.

When you trust the staffers you've hired after putting in considerable due diligence, you get to reap more of the rewards of their output.

There are many different paths to serial entrepreneurial success, but all require having solid teams in place, delegating appropriately and trusting that these people will act in your organization's best interests.

Listen to the stories your data tells you.

You can learn almost anything about your companies by spending time on the ground level of various departments: listening in on customer service calls, observing interactions between salespeople and clients, watching operations teams go through manufacturing processes and so on. Although you should schedule regular time for these activities,that's impractical.

What you can do, on a weekly basis at minimum, is read through the data reports from all your ventures, to stay on top of things. In an interview with McKinsey & Company, Victor Nilson, senior vice president of big data at AT&T, shared an example of his organization's approach to data-driven decision making: "We've used big data techniques," Nilson said, "to analyze all the different permutations, to augment [the customer experience] to more quickly resolve or enhance a particular [customer care] situation.

"We take the complexity out and turn it into something simple and actionable."

Modern data analysis is remarkably powerful and intuitive, and by monitoring your results regularly, you can easily discern patterns and trends that tell important stories about the trajectory of your companies. This way, you'll have access to solid evidence that can help you decide when you need to get more actively involved in a particular situation.

Keep your schedule as meticulous as possible.

We all understand the reasons why schedules get out of sorts: Meetings run long, traffic is backed up, flights get canceled; and these are just a few of the possible unexpected and unpredictable occurrences. You can't control the weather or the traffic; and you can't expect your carefully curated schedule to remain pristine all the time, as you juggle your various responsibilities and meet with diverse groups of stakeholders for your businesses.

However, you can't let that lack of control be an excuse for not keeping to your schedule as diligently as possible, or, worse yet, not even outlining one to begin with.

As the leader of multiple companies, you need to consider that your time is too valuable to be left up in the air, even if things don't always proceed as expected. When time tables get off track, accept it and do whatever it takes to get things back on schedule as soon as possible.

Organize "theme days" for deep strategic dives

As a matter of fact, optimizing your time is so important that some serial entrepreneurs have turned it into an art form.

When Jack Dorsey was in charge of two of the most innovative and noteworthy tech companies in the world at the same time, Twitter and Square, he maximized his time spent on various tasks by funneling them into what became known as theme days.

Dorsey said of the strategy, "The way I found that works for me is I 'theme' my days. On Monday, at both companies, I focus on management and running the company . . . Tuesday is focused on product. Wednesday is focused on marketing and communications and growth. Thursday is focused on developers and partnerships. Friday is focused on the company and the culture and recruiting.

"Saturday I take off; I hike. Sunday is reflection, feedback, strategy and getting ready for the week."'

Learn that email is your best friend . . . seriously

With so many different mediums available for communication these days, is email still important for business leaders? Actually, it's probably the most valuable digital tool in your arsenal. It's one of the few ways you can effectively multitask across your various companies, no matter where you are currently located.

Take it from one of the most renowned multi-company entrepreneurs, Elon Musk. Speaking at a 2013 conference, about productivity, Musk reportedly said, "I do a lot of email -- [I'm] very good at email. That's my core competency." He said it humorously, of course, but everyone knows that truth always lies at the core of a joke. If you hope to manage your time efficiently, you have to stay on top of your emails relating to all of your ventures.

You may be tempted to forward your emails to one inbox; but I've personally learned that that's a surefire way to make prioritizing tasks difficult and to make you feel overwhelmed by all those incoming messages.

So, to oversee Amerisleep and OCLU effectively, I keep my emails for each venture separate and block out time to address messages from one before switching to respond to emails I received in the other.

Know when to say no.

As you start building multiple successful businesses,the tempatation may be to throw your hat in the ring with every opportunity that comes along. Entrepreneurship is a skill, after all, and like all skills you tend to get better at it the more you practice.

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This is when it becomes important to analyze risk carefully and know your limits. Richard Branson, another well-respected serial entrepreneur, said, "You need to learn when to go forward and when to say no, which can be difficult — especially if you prefer to say yes, like I do!"