An entrepreneur's life is one of frequent rejection from both potential customers and potential investors. So learning to handle rejection correctly is an essential survival skill.

Just ask Julie Corbett, founder and CEO of Ecologic Brands, which produces molded-paper bottles with a plastic pouch inside as packaging for products traditionally sold in plastic bottles. The cardboard bottles are fully recyclable, and made from recycled cardboard boxes, using as much as 70% less plastic than the bottles they replace.

Corbett was inspired to create the bottle after seeing the molded fiber cardboard in the packaging of her new iPhone and was struck by both its appeal and its potential as a packaging material. She suffered from poor timing, though: She launched her company in the spring of 2008, just in time for the financial crisis. Investors turned her down flat.

"All entrepreneurs believe they have the best idea in the world," she says now. "What tests you is always rejection. You either continue to be bull-headed, or you give up."

How can you handle rejection without letting it bring you down? Try these tips:

1. Accept that you'll hear 'no' much more often than 'yes.'

Most founders looking for new investors or new customers get turned down more often than not. This was especially true for Corbett who did not initially have a product to show. "When I was trying to convince angels to give us money, I had my iPhone molded fiber case in one hand and a plastic pouch in the other and I was saying, 'Imagine a bottle using these two elements.'" Most of them couldn't, she says. "There's a small sliver of people who can visualize something like that and go there with you. The vast majority don't have the bandwidth or the interest or the belief."

2. Take it as a compliment.

Yup, you read that right. Of course, a bad idea will get lots of rejection--but so will anything truly innovative. Most investors--and even TechCrunch Disrupt judges--are much more comfortable with a slight variation on a proven business idea than with anything genuinely new.

"The me-too products for Ecologic will have life so much easier than I did," Corbett says. "Creating something completely new you take a lot of cuts and scrapes along the way because you have to prove that your product fills an unmet need. It's like taking a machete through the jungle."

3. Show off your product whenever you can.

Throughout the process, and to this day, Corbett carries an Ecologic bottle wherever she goes. "Investors might say no, co-manufacturers might say no, but whenever people saw the bottle peeking out of my bag on the street or on BART, they'd always ask me about it." Once, she walked through a factory carrying a bottle and many of the factory workers left their posts to take a closer look. So Corbett knew for sure that consumers would love it. "That's one thing that sustained me," she says.

4. Surround yourself with believers.

"Naysayers are important because they're a sounding board and they tell you what to focus on," Corbett says. "You have to listen to them but you can't take it to heart. You have to surround yourself with people who believe in you, not just people saying 'Oh, that's cool!' but those who are actually willing to help."

For Corbett, creating that "ecosystem" of supporters was instrumental. Among them were the leaders of Straus Family Creamery, who agreed to a test, delivering milk to people's homes in Ecologic bottles. Response was overwhelmingly positive. "I hoped that would lead to the funding I needed," Corbett says. "But a lot of investors said, 'Fine--you've shown that a bunch of consumers will use it at home, but will they buy it?'"

So Corbett went back to Straus and the creamery used its relationship with Whole Foods to get an in-store test. Because Straus milk is unhomogenized, and the cream top might confuse some consumers, Corbett decided to test the bottles on nonfat milk only. "There was no promotion whatsoever, but during the test they sold 72% more nonfat milk than they usually do," she says.

Those results got attention not only from investors but also from Packaging Digest. The trade magazine's story on Ecologic caught the eye of many manufacturers, including Seventh Generation, which began using the bottles for some of its laundry detergent line. Thanks to this giant customer, Ecologic recently celebrated the sale of its millionth bottle. And stay tuned, Corbett says: More brands will begin using Ecologic bottles over the next few months.