When it comes to picking business opportunities, it may be tempting to latch onto the next hot thing, but it's also important to invest in industries you know well.
That's one key takeaway from billionaire entrepreneur and "Shark Tank" investor Mark Cuban, who shared five business strategies, some of which may surprise you.
Before starting a business, Cuban does extensive research on an industry to see whether the opportunity is compelling and potentially profitable.
"It really does involve knowing an industry well, which is why I avoid investing in industries I don't know," Cuban posted on the private messaging app Cyberdust on Wednesday. Cuban reposted advice he gave for a class project through the app.
"You need to turn over every rock and open every door to learn your industry. This process never ends," he said.
Below is a screenshot of Cuban's advice.
If you think your business plan is set in stone, think again. Cuban stressed the importance of leaving business plans "open for change."
Getting cash for your business is essential, but there's a right way to do it.
"You should do everything possible to not raise funds. Sweat equity is the best equity. I would turn to crowdfunding like Kickstarter before I would look for investors."
"You execute better than they can," he wrote. "Do a better job and have a compelling differentiation that you always build on."
Entrepreneurs shouldn't start a business if an industry is already crowded, Cuban said.
— CNBC's Sandy Maltzman and Michael Bloom contributed to this report.
Disclosure: CNBC owns the exclusive off-network cable rights to Cuban's "Shark Tank."