Last month, during Austin's SXSW festival, Inc. brought together a host of high-profile business executives and innovative entrepreneurs at the Founders House. Naturally, it was a group that was highly experienced and savvy in the art of networking. Some of the luminaries in attendance passed on their best tips for making connections at such events or anywhere you're trying to meet potential business partners and develop new opportunities. Here are their five key lessons.

1. Do your homework before formally networking.

Get to know the person you plan on talking to in advance. By doing thorough research, you should gain a rough idea of how you can appeal to that contact, says Elizabeth Gore, the president of Alice, an A.I.-based adviser for business owners. But professional relationships should benefit both parties. "Really think about that two-way connection," Gore advises. When you approach someone, know what you can offer that person to make the interaction more memorable, authentic, and distinct. 

2. Adhere to the '48-hour rule.'

After a business meeting or conference, or even just a quick chat over coffee, Gore says, it's crucial to follow up within a short time frame. Once she parts ways with a potential professional contact, she puts a reminder in her calendar to check back within 48 hours. Getting in touch any later than two days after meeting someone can give the impression that you don't care about the new relationship or the subject you discussed with your new contact.

3. Be cutthroat in what you want.

Cindy Eckert, founder and CEO of the Pink Ceiling, a venture capital fund that invests in female-led businesses, preaches the value of persistence. She advises being upfront and tenacious in letting people know what you are out to accomplish--an approach that served her well on her path to entrepreneurial success. "You have to be convinced that you would be doing the other person a disservice by not telling them what you're trying to do and how you're trying to change the game," says Eckert, who has sold two pharmaceutical companies for a total of $1.5 billion. "That is the mark of a true entrepreneur. They're so determined that everybody will hear their vision."

4. Don't ask this question.

Never ask somebody what he or she does immediately upon meeting that person, says Stephen Lease, the founder and CEO of sunglasses startup Goodr: "That is the lamest way to network possible." Being authentic is key--which means skipping the small talk. The best professionals will approach a networking opportunity with fresh questions. Find a conversation topic to connect on, Lease says. Once you hit on something that can bond you with a prospective contact, you have better odds when it comes to asking that person for a favor.

Bonus tip: If your company sells a product, like sunglasses, always have a sample on you to give away when you meet someone, he adds. That's how you leave a lasting impression. 

5. Carry yourself with a cool confidence.

"A good $50 to $100 million of our cap table came from random introductions," says Chieh Huang, the co-founder and CEO of Boxed, an e-commerce company. Huang says it all comes down to being confident. "Go up to folks whether you know that they can help you or not," he says. Greet them and ask them what they are talking about. "In my entire professional career, I've never gone up to a group of folks and asked that question and been rejected."