Richard Branson, Shaquille O'Neal, Daymond John and others reveal what they wish they knew at 25 years old

Hindsight is always 20/20. These moguls and advisors from The Oracles, a mastermind gr­oup of high-level entrepreneurs, share what they would tell their 25-year-old selves if they could go back in time.

I would tell myself, "Congratulations on launching Virgin! Stick with it, because the best is yet to come. Don't stop working hard to make your wildest dreams come true. There will be many times where you think it will be easier to give up. Don't.

"You'll learn to turn challenges into opportunities and find the success you never imagined you could achieve. Know that it's okay to fail — that's just part of the entrepreneurial journey. The Virgin brand will take you other places than music, so grab every opportunity that comes your way. And make sure you keep smiling and have fun."

— Sir Richard Branson, founder of the Virgin Group, which controls more than 400 companies; investor, author, and philanthropist; previously named one of Time's 100 Most Influential People in the World

If I could write a letter to myself when I was 25, I would tell myself to save. Spend accordingly and value everything.

Don't waste time chasing useless titles. For example, what does it mean when people say, "You're the man"? You become "the man" the day you fulfill your own dreams.

And finally, continue to enlighten people and make this world a better place by brightening a stranger's day.

— Shaquille O'Neal, former NBA player, entrepreneur, investor, and philanthropist

I closed FUBU three times when it first started, and it challenged me in different ways each time. Accept that failing is part of the process. When you do fail, see it as an opportunity to grow and then apply those lessons immediately.

— Daymond John, Shark on "Shark Tank," NYT-bestselling author of Rise And Grind, creator of Daymond On Demand, and founder of FUBU

I would tell myself that ceilings are created by our own fears and insecurities. There are no boundaries. Your goals are limiting your potential, so aim beyond your reach.

I grew up in a household with entrepreneurs. I watched them experience a little success and then extreme hardship. I became conditioned to think safe, to have dreams and goals, but to keep them attainable and realistic. That thought process was crippling to me for a long time. I was scared of repeating what I had witnessed.

When I met my husband, I quickly realized he was a visionary. I struggled to see what he saw for our lives together. He dragged me along until he finally helped me free my mind. I started thinking so big I had to laugh at my audacity.

Looking back, I can't believe how much time I wasted stuck in that small-minded mentality. Once I let that thought process go, I grew into the person I am today.

— Jessica Mead, co-founder of EpekData and BrandLync, divisions of Mead Holdings Group, Inc.

As a leader, people will always ask you for favors or help with their problems. I try to help them when I can. But you need to protect your time and honor your priorities. If you say "yes" and are always stressed out and overwhelmed, it's your own fault.

Time is our most precious commodity. Learn how to say no and carve out space for what matters most to you. It's hard to have it all. You can't be great at every single thing, but you can learn to balance your time.

— Dottie Herman, CEO of Douglas Elliman, a real estate brokerage empire with more than $27 billion in annual sales

Most people think their 20s is the time to travel, take time off and explore. Forget that. It's the time to go all in and make the sacrifices your friends aren't willing to make. You'll never have more energy and less responsibility in your adult life.

I would tell myself that the amount of money you make is directly correlated to the big problems you can solve. Take doctors and lawyers — they save lives and keep you from jail. Both require large investments and years of education, and people pay a premium for them. How many problems can you solve? If you can't solve any, master something you thoroughly enjoy that people need.

— Billy Gene Shaw III, founder and CEO of Billy Gene Is Marketing

At one point in my career, I was writing copy and making clients a lot of money — sometimes 10 to 100 times what I was billing them. But I just couldn't ask for more money. I also didn't think I could be a musician, but after my divorce, I felt like I could do anything. I wrote a few albums, got signed and went on tour.

I would tell my younger self, "Craig, limiting beliefs in what you can ask for and accomplish will hold you back more than anything else. Believe in yourself, the universe, and a higher power. Put what you want out there. That will open doors and guide you."

— Craig Handley, co-founder and CEO of ListenTrust

I learned early in my career that I needed mentors to supercharge my growth. I thought the only way to get to them was to beg for a lunch or coffee meeting to "pick their brain." Successful people have no time for that. They need to know you're serious first.

If I could go back, I would pay for access. That is the ultimate sign you're serious, and a small price to stand on the shoulders of giants. I have written big checks for coaches and to join professional groups which have helped me grow my business, optimize my health, and launch a global business in 90 days.

— Sharran Srivatsaa, angel investor and CEO of Kingston Lane

I would ask myself why I insist on creating new products and trying new ventures. What if you just focused all your energy on one thing and making it the greatest thing ever? You'll do well even if you try to do 100 different things because you're relentless, but you'll spread yourself too thin.

Your capacity multiplies when you focus on one single thing. You're not missing out when you say "no" to other opportunities. You're playing the game like the best do: with a singular, laser focus.

— Jason Capital, author, high-income coach, online marketing expert, and founder of High Status

I wish I knew to trust myself more when I started my business. If I could go back, I would tell myself, "Ines, things are not happening against you, even if it seems that way. They're happening for you. It seems hard, but the universe always takes you down the right path. All of the hardships and struggles will be worth it.

"So follow the breadcrumbs, even if it doesn't always make sense. And follow your gut, because it is your greatest asset. Always stay true to yourself and don't try to blend in. What makes you different helps you stand out and succeed."

— Ines Ruiz, former Cambridge University professor, founder of Pocket Learning Spanish and Diary of an Entrepreneur

I would tell myself not to take everything so seriously. What you have is enough, so be diligent with it. Make a plan and commit to the outcome. Still, be flexible in your approach and open to the twists and turns that naturally happen in life.

Work hard and have fun. Treat those who walk alongside you for a season as great friends, and help them in their journey.

Focus on what you enjoy. Be grateful — you'll do everything better when you have a positive attitude. Commit to self-development. Continually expand and explore with a sense of adventure and curiosity.

— Lin Sun, CEO at Tiny Devotions and partner at Crimcheck

Think bigger than your circumstances (and your bank account). Don't be afraid of failing — be afraid of not failing.

Just because you can doesn't mean you should. Be careful of your promises and who you make them to. When others' actions reveal who they are, believe them.

You get earned income from good work, but you get passive income from good decisions. You can't put a price on inner peace and a happy heart. Don't settle for less.

Read great books. Wear sunscreen. And if you forget any of this, don't worry — you'll learn the hard way.

— Shaun Rawls, author, entrepreneur, founder and CEO of Rawls Consulting

The Oracles is a mastermind group of the world's leading entrepreneurs who share their success strategies to help others grow their business and build a better life. Follow The Oracles on Facebook for more articles like this.

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