Any entrepreneur knows failure is a staple of life. They make mistakes, they learn from them. If they're lucky, they have friends who've already made those mistakes and can preemptively teach them the lessons.
One thing I always try to keep in my professional life is some form of mentor. This person should be someone who has accomplished something that you admire - someone who can inspire you to be better, but can also help get you there.
I won't count family as mentors - while they certainly are, their levels of bias are generally too high (they want to blindly support you, and may lose some objectivity - they'll often fight for you, even when you're dead wrong).
I've had 5 amazing mentors so far, here are some of my takeaways to-date:
My first mentor was during college - a professor who taught entrepreneurship. He was one of my first freelancing clients. Even though I really enjoyed his class, the more valuable lessons I learned through working with him. It was about his shotgun approach to business that stuck with me the most - not the football formation - but the idea that trying out a lot of ideas and focusing on the ones that stuck made sense. I read all about people who started XYZ, and lived and dreamed the business - which inevitably lead to their success. Its not that I disagree with that approach, its that I dislike the cult attitude surrounding it. You don't need to bleed an idea for it to be successful. It's ok to try things just because you want to see the response. Overcommitting to things before they're successful will make it that much more difficult to quit when you hit the dip, and even harder to come to terms with if it fails (which most businesses do). Try a lot. Test everything. Save your passion for the things that have proven to be worth it.
My second mentor is a close family friend. I worked with him for about 6 months after college - he helped me determine wether or not it was worth launching a business around a fitness program I had been designing and planning for throughout my college career (read: overcommitting). I learned more during my time with him than I did all 4 years in college. Its depressing how much I truly mean that (good old student loans). The people I was introduced to, and the lessons around startups he ingrained into me were priceless. I'm sure I'll blog more about this later - but one of my greatest takeaways while working under him was the importance of customer development and market research. Selling a product to customers that don't exist is insane - but people do it all the time. Most businesses fail for that reason. People assume their idea is the absolute best thing since star wars, and don't realize only the sith deal in absolutes. To be clear - make sure your customers are real, and want to pay for your product before you go about building it.
My next mentor was completely different - he was technical mentor. We worked together and he pushed me to be a better designer. He taught me different techniques for achieving different effects through CSS, and in photoshop. I can't express how important mentors like these are - they will increase your value ten-fold, and unless you're a dumbass you'll make a really great friend.
My last two mentors I'm currently working with, and they'll probably read this at some point so I'll leave it at this:
Your mentors surround you. They're smarter than you. They're better than you. And they can teach you some serious shit. If you're not surrounded by people like that, than you're working in the wrong fucking place.
Giving it back
In the same way that I'm always actively trying to be mentored (which effectively means I ask a shit load of questions all the time, with the goal of understanding reasoning - not just accepting an answer blindly) - I'm always happy to help my friends and co-workers in the same sense, wether its talking about business, attitudes towards culture, design or anything else where my experience may be greater - because if you're not paying it forward, than the value of your experience is lost into the ether.