How to ask for the biggest raise possible and get it, according to 'Shark Tanks' stars

Before you gear up to ask your boss for a raise, "Shark Tank" stars and business gurus Barbara Corcoran and Robert Herjavec shared some of their top tips and must-know advice on how to construct a winning pitch to ensure you walk away with the biggest pay bump possible.

A nurse practitioner and professor plus technology consultant who are hoping to score raises practiced their pitches with Corcoran and Herjavec, who gave them both feedback on how to put their best foot forward.

Ask for 'more than you want,' but know 'raises are a process'

Bernadette, the nurse practitioner, told "Good Morning America" that she hasn't had a pay increase in five years.

Her pitch: "I'm here asking for a 30 to 40 percent raise because I believe the work I provide for this organization does not currently match my salary."

Right off the bat, the sharks were stopped in their tracks.

"30 to 40 percent is a big increase," Herjavec said, adding that most businesses give raises of approximately "8 to 10 percent."

"You shouldn't ask for something that big," he added. "Because you're going to shock somebody."

While asking for 30 to 40 percent may be too much, Corcoran does recommend always asking for "more than you want" by "a little."

"Raises are a process," Corcoran said. "You don't walk in and hit someone over with a giant club -- sometimes you get there with little clubs along the way."

Ask for a 'path,' and 'create a plan' if your looking for a major bump

Herjavec recommended asking your supervisor for a "path" to help justify a bigger increase.

"You always do better negotiating something over a term," he said. "As opposed to, today, asking for 40 percent is harsh, whereas if you came in asking for 12 percent today, but you hope one day to make 30 percent, and could I show you a path to get there."

Corcoran added that it is a good idea to "create a plan."

Show your value explicitly

Meanwhile, Ann, a professor during the school year and 3D printing technology consultant in the summer told "GMA" that she is hoping to increase her consulting rate by $1,000.

Her pitch: "My rate ... was $4,500 and this year it's $5,500. Some things have changed," she told Corcoran and Herjavec. "In addition to my experience, I'm doing a little bit more research on your behalf and setting you up with a couple of more success points."

She said she feels she should get $1,000 more "because I'm able to quickly identify other things that institutions typically also need that I wasn't providing previously."

Corcoran presses Ann for a better reason.

Ann adds that her clients will be “getting classes” and “a structure that helps them communicate their success to their constituents. So we’re talking about measurable outcomes.”

It’s the “measurable outcomes” that the Sharks agree is her selling point for the rate increase. Essentially showing what someone is getting, not the process.

Corcoran said that getting a raise always comes down to how valuable you are to the company or the client.

Be specific

Corcoran recommends that Ann should start with specific examples of how she will benefit the institution.

"I think where you should start is I was here last year, I did work with you," Corcoran said. "And then you have to say the difference from last year now is now we do a ton more for you specifically this and this is how it will benefit you."

Herjavec added to always start by discussing your value to them.

"People don't buy you for what you do," he said. "People buy you for what you do for them."