Mark Cuban sold his first company for six million dollars and his second for six billion. He cashed out his Yahoo stock for another two billion just weeks before the market crashed. He owns a cable channel and an NBA team, and he's accomplished exactly none of this by soft-selling his opinions or keeping them to himself.

Cuban has invested in hundreds of companies and is partnered with well over a hundred entrepreneurs at any given point in time. If you are blessed to partner with him, he will expect from you a weekly report with both the good news and the bad news. Of course, he likes to read the bad news first to really know what's going on. He is constantly evaluating the performance of his partners. Needless to say the good get to keep doing business with Cuban. The bad are strongly encouraged to seek career development elsewhere.

Here's what Cuban says to do and not do if you want to succeed in the high-stakes world of entrepreneurship.

Don't

  1. "Leaders don't conform to the consensus. They create consensus to their vision and goals."
  2. "When you've got 10,000 people trying to do the same thing, why would you want to be number 10,001?"
  3. "There are always going to be things we love to do. That we dream about doing. That we really, really want to do with our lives. Those passions aren't worth a nickel."
  4. "In my opinion, right now there's way too much hype on the technologies and not enough attention to the real businesses behind them."
  5. Wherever I see people doing something the way it's always been done, the way it's 'supposed' to be done, following the same old trends, well, that's just a big red flag to me to go look somewhere else."
  6. "Don't start a company unless it's an obsession and something you love. If you have an exit strategy, it's not an obsession."
  7. If you have managers reporting to managers in a startup, you will fail. Once you get beyond startup, if you have managers reporting to managers, you will create politics."
  8. "Small businesses don't fail for lack of capital. They fail for lack of brains, they fail for lack of effort."
  9. "Leaders don't change their positions mid-debate. They welcome scorn from the masses because it creates the opportunity for dialogue."
  10. "You should do everything possible to not raise funds. Sweat equity is the best equity. I would turn to crowdfunding [sites] like Kickstarter before I would look for investors."
  11. "A sure sign of failure for a startup is when someone sends me logo-embroidered polo shirts. If your people are at shows and in public, it's okay to buy for your own employees, but if you really think people are going to wear your branded polo when they're out and about, you are mistaken and have no idea how to spend your money."

 Do

  1. "Work like there is someone working 24 hours a day to take it all away from you."
  2. "Whatever business you have, there is always someone trying to put you out of business. It's better for you to figure how they're going to do it, than they do it."
  3. "Once you have found out what you love to do, there is only one goal: to be the best in the world at it."
  4. "You've gotta be differentiated and unique. You've gotta know what your core competency is and be great at it."
  5. "I'm the one guy who says don't force the stupid people to be quiet -- I want to know who the morons are."
  6. "Relaxing is for the other guy. I may be sitting in front of the TV, but I'm not watching it unless I think there is something I can learn from it. I'm thinking about things I can use in my business, and the TV is just there."
  7. "I worked hard and smarter than most people in the businesses I have been in. It's not in the dreaming, it's in the doing."
  8. "I still work hard to know my business. I'm continuously looking for ways to improve all my companies, and I'm always selling. Always."
  9. "It is so much easier to be nice, to be respectful, to put yourself in your customers' shoes and try to understand how you might help them before they ask for help than it is to try to mend a broken customer relationship."
  10. "It's not about money or connections--it's the willingness to outwork and outlearn everyone...And if it fails, you learn from what happened and do a better job next time.
  11. "It doesn't matter how many times you have failed, you only have to be right once."