Here are three steps for finding the most experienced mentor to help bring your startup idea to the next level:

1. Recognize what makes a great mentor.
At TechStars, we've found that the best mentors are those who ask a lot of tough questions and challenge you to exceed your goals. In doing so, they should share their own experiences and help you uncover new opportunities.

But the best mentors shouldn't tell you exactly what to do. They understand their role as an advisor and that it's your company to run, not theirs. Those who tell entrepreneurs what to do, and become upset when their instructions aren't followed, often cause more damage than good.

Think about approaching the founders and key executives of companies in your space who you admire. Those people are usually more likely to invest time in your business than those with crushing demand from strangers.

To make that first connection, you might try sending a short email explaining what your startup is doing and why you are reaching out. Avoid "form" emails and always make it relevant and easy for the prospective mentor to help. Take a few minutes to read the person's blog or Twitter account and learn about his or her background so you can personalize your note.

Most of the cold emails I receive from entrepreneurs start off by requesting a meeting over coffee. While this might seem like a good first request, it isn't always. For example, I'm an introvert who doesn't drink coffee. Even if I did, I'd have to leave my office to meet with the person and most busy mentors won't initially have time to meet.

Build up to that first meeting by establishing a rhythm of interesting and thought-provoking email communication. Demonstrate that you're making regular progress on your product and close the feedback loop so the mentor knows you're listening, analyzing and reacting. When you do eventually ask to speak face-to-face, request a 15-minute meeting at his or her office.

Approaching a smaller number of mentors who have an actual connection to your business or your market and making sure they understand that connection early on usually leads to better long-term engagement between the mentor and the mentee.

2. Find a good fit.
A common mistake we've seen is going straight at the busiest, most well-known, most visible mentors. While this may occasionally work, it's often more productive to analyze your own close network and look locally for mentors whom you respect with relevant experience.
Great business mentors can have an enormous impact on early-stage startups. Their connections can open doors that would otherwise be closed and their experiences can save entrepreneurs from suffering from the same startup mistakes they've already made.

But finding the best mentor for your business isn't as simple as picking a name from a hat. You'll need to be able to recognize what makes a great mentor, know how to approach one and then how to maximize the relationship. At TechStars, the mentorship-driven seed stage investment fund I co-founded in 2006, we've seen all types of mentor relationships, successful and not.

3. Maximize the mentor relationship.

Once you've established a connection, and there is interest from both sides, it's important to build a relationship over time. One way to do this is to check in regularly by email. Mentors should love to see your progress and take pride in knowing that their input has been helpful. Send a monthly email that reminds them of your past conversations and updates them on your progress.

Ask one new question in these emails to ensure the conversation continues. It's important to keep these check-in emails short and to the point and not ask for too much at a time. For example, requesting a two-hour phone call once a week is probably going to be an unrealistic demand. Getting together at the mentor's office for 30 minutes once a quarter can be an easier request to be fulfilled once you've established a real relationship.