Last month, the 12 startups in Techstars NYC 2015 winter class presented at the accelerator's demo day, delivering concise pitches in front of an audience of hundreds of investors.

The presentations capped of a whirlwind three months at the accelerator. Having since officially graduated from the program, the entrepreneurs behind the graduating companies share some of the best advice they learned at Techstars as well as what they'd do differently if they could repeat the experience again.

1. Make more connections.

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Start utilizing the network earlier. The Techstars network is very powerful and wide reaching, but it doesn’t just come to you (most of the time). You’ve got to put the work in to figure out who can help you and reach out to them.

-- Ariel Briner, co-founder and CEO of Cartesian Co.

2. Create time for mentors.

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I'd engage more mentors. I wish I had all the time in the world to do so. There are so many incredible people that can make a difference for your business, and you have limited time to work with all of them.

-- Joseph Fasone, founder of Pilot

Techstars gives us a unique opportunity to connect with high-level mentors. Their feedback is priceless as most of them are entrepreneurs themselves and know exactly what you are going through. But the program is so intense; it's easy to pass on this opportunity.

-- Jeremy Boissinot, COO of Keymetrics

3. Concentrate on growth.

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To get the most out of the program, companies should be ready to accelerate. We had some product work we needed to do before we could take full advantage of the opportunity to grow quickly. There was no way around it -- but it would have been ideal to just step on the gas pedal.

-- Krystle Mobayeni, co-founder and CEO of BentoBox

4. Treat mistakes as learning opportunities.

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The whole Techstars experience has been incredible, and a massive challenge. During the program we've met hundreds of fellow entrepreneurs, investors, and mentors, all with different experiences and opinions. As a result it can be tough to both stay focused and confident…Of course we could have avoided some missteps here and there, but I feel that every mistake we've made, and will make, will serve us in the future.

-- Satish Naadimuthu, co-founder of Stefan's Head

5. Take care of all conceivable logistical headaches before the program starts.

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I would have done taxes in early January and fully moved our office to the city before the program

-- Shane Scranton, co-founder of IrisVR

I would have gotten my B1 visa well in advance of the program.

-- Thierry Schellenbach, co-founder of Stream

We would have expanded the team before Techstars started, instead of during.

-- Tommaso Barbugli, co-founder of Stream

6. Get moving.

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Make more of an effort to get out of the office and exercise!

-- Mackenzie Barth, co-founder and CEO of Spoon University

7. Nail down your source of caffeine.

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I would bring with me good coffee from France ;)

-- Romain Cochet, co-founder and CEO of Unique Sound

8. Plan ahead.

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In one word: Preparation. For various reasons, the two months before we joined Techstars were really hectic (preparing the move of the team and the company from Belgium to the U.S., raising some capital at the last minute). We were able to accomplish a lot in Techstars' three month program, but could have done a better job preparing before the start of the program. I would advise future participants to start their preparation the day they’re accepted. It’s hard to imagine how quickly things start to happen once the program starts.

-- Jonathan Cornelissen, co-founder and CEO of Data Camp