You want bootstraps? Robert Herjavec's got bootstraps. The entrepreneur, investor, and Shark Tank star arrived in Canada after fleeing the former Yugoslavia, and worked his way up from nothing. He delivered newspapers. He started a computer company in his basement. And today? He's a highly sought-after speaker, a well-known investor, and popular television personality. As if that's not enough, he's also at the helm of the Herjavec group, a global leader in information security.

But things still aren't always easy for Herjavec: after his divorce, he hit rock bottom-- and even contemplated suicide. But that experience motivated him to keep working and striving for success.

According to Robert Herjavec, here's what it takes to be a successful leader. 

1.  If you want to succeed, be ready to ready to face failure.

While Herjavec struggled after his divorce, he knew that bouncing back was crucial. As he puts it, "Success is not measured on the days when the sun shines. Success is measured on the dark, stormy, cloudy days. And if you can't absorb failure, you're never gonna meet success."

The key to being successful, as an entrepreneur and as a leader, lies in preparing to face failures and finding the opportunity in each and every one of them.

2.  A good leader balances empathy and forcefulness.

As the founder of multiple companies, Herjavec is no stranger to the challenges of leadership. He says that the best boss is one who knows, understands, and is compassionate toward their employees, yet doesn't compromise when it comes to achieving goals.

"I'm a great guy to work for 98 percent of the time, but the other 2 percent of the time, you're going to do it my way, and that's it," he says. "A great boss is kind, but you have to strong, too. You can't be a pushover."

As a boss, you can't always be the good guy, and you can't always be an employee's best friend. Don't be afraid to be demanding and tough when necessary because that's how you achieve your goals.

3. Seek out mentorship and advice,  but do what's right for you.

Herjavec was lucky to connect with entrepreneurs who mentored him early on in his career. But he emphasizes the importance of not just following and mimicking what people have done before.

"I'm pretty good at taking value from people's opinions, and discarding stuff that I don't think is relevant to me," Herjavec says.

Seek out and learn from mentors as a means to learn the ins-and-outs of business and leadership. So take the lessons you get from your mentors and focus on the things that are relevant to you, and don't be afraid to pursue your goals, even if doing so might contradict a mentor's opinion. Innovation does not come from following in someone else's path.

4. Learn from the mistakes of others and execute better.

In this video, Herjavec points out that there are no new ideas under the sun; everything has been thought of before. So when you're looking for a new business opportunity, don't reinvent the wheel, instead look to the products, services, and ideas that people have tried out in the past --and find ways to innovate where others have failed.