This social media hack could help cash-strapped entrepreneurs compete with big brands

If you dream of becoming the next Jeff Bezos, or simply fancy yourself as a side-hustler, but worry you lack the cash; fret not — it needn't cost you the world.

In fact, one of the most effective ways to get your idea off the ground could be with a free hack: testing out products on social media.

It's a tool used by Supernova, which, despite enjoying runaway success with its beauty lines SkinnyMint, Sand & Sky and BodyBoss, still rates the frugal, start-up strategy among the best.

Supernova is what's known as an incubator, meaning it uses industry insights to identify demand for new products, and then assembles a team to create them and bring them to market.

However, when testing out those new ideas, the business doesn't spend a penny on building prototypes, Supernova's co-founder Emily Hamilton told CNBC Make It.

Instead, it uses Photoshop to create mock up images, then shares them on Instagram and gauge customer interest.

Only once the company has identified demand — for instance, through customer requests — does it invest money in creating the product, said Hamilton.

"People can sign up to register their interest in a particular product and then we know whether it's worth pursuing," Hamilton explained.

"It's something we've done from the beginning," she continued, referring to the launch of its first line, SkinnyMint, in 2014.

The tactic is a far cry from the product development methods of old and those typically still used by more established brands with bigger budgets.

In an interview with CNBC's Adam Shaw last month, L'Oreal's operations chief digital officer, Stephane Lannuzel, said the company was leveraging new technologies to improve its processes.

Rather than using free methods, though, L'Oreal is investing heavily in 3-D printing to cut down the time required to bring products to market. Last year, the cosmetics giant used the technology to create more than 15,000 prototypes.

However, Hamilton said that trialing products on social media goes beyond simply providing a cheap fix for cash-strapped start-ups. It also give an insight into customer demands that goes beyond traditional methods.

"Ultimately, you want to know that the product is going to sell," noted Hamilton. "Big corporates can invest a lot of money in focus groups and things. But if you don't have the money, you can go to social media and get real feedback — and it's also more likely to be genuine feedback."

Having that direct line of communication with consumers has also made it easier for entrepreneurs to identify new opportunities, according to Hamilton.

"There's a huge market for product discovery these days, so we're creating niche brands that really appeal to the consumer," she said. "Social media gives you that opportunity to see what other people are saying."

Hamilton is not alone in using social media for inspiration. Fellow Australians Alex Tomic and Nik Mirkovic built their now-$40 million teeth whitening brand HiSmile on the back of a trend they identified on Instagram.

Like Hamilton, the duo relied largely on social media and influencers like Kylie Jenner to promote their brand and build a following.

More established brands are also cottoning on to the new opportunities social media creates for product innovation.

For instance, U.S. clothing line J. Crew recently experimented with polling customers on new products using Instagram Stories. It presented two different colored jumpers and asked viewers to vote on which one it should create.