The actress hosted "Live! With Kelly and Regis" -- now "Live with Kelly and Ryan" -- from 2001-2011 after Philbin had spent decades hosting television.
In a preview from ABC's upcoming special on the late TV icon, Ripa, 49, opened up about working with the legend.
"I think my biggest takeaway from the 11 years that I shared with him was that you have to be yourself," the former soap star said. "You cannot be one person on camera and a different person once the light goes off or the audience is gone."
She added: "You have to be who you are."
Similarly, the Daytime Emmy winner said Philbin's "talent was being himself completely and making everybody else the star of the show."
"I think his love of people will also be his legacy," she said.
Ripa also disclosed her thoughts upon hearing the news of Philbin's passing.
"It was this moment -- and my daughter sort of crystallized it for me -- Lola said: 'That's gotta be a mistake. That can't be right,'" she recalled. "And there was a moment where I had this incredible hope that it was somehow misreported."
Ripa also explained that after hearing the sad news, her thoughts went out to Philbin's daughters Joanna and J.J., his wife Joy and Kathie Lee Gifford, who hosted alongside Philbin before Ripa stepped in.
It wasn't just the actress who was close to Philbin, however, but also her children, who Philbin once babysat, as was captured on camera in clips that made Ripa feel "particularly emotional."
"There's a moment where Regis is brushing Lola's teeth and she's staring at him, and he says to her: 'You're a genteel little [woman],'" she remembered. "Just the way he spoke to her in this very sweet way."
The special, "Regis Philbin: The Morning Maestro," was set to air Tuesday night on ABC at 8 p.m. ET.