The 31-year-old actor says she was in awe of Akhtar and working with him was an "exhilarating" experience.
"He is a multitalented person. Initially I felt slightly intimidated by him... I was a bit nervous, but later it all turned out well.
"I am thankful to him for making me feel comfortable. There is a lot to learn from him," Diana tells PTI.
The 'Cocktail' actor says before they started shooting for the movie, the duo did a couple of reading sessions to break the ice.
"It was an opportunity to come together, work and give our best. There was never any problem working with him, I guess I just made it (referring to feeling intimidated) up in my head."
Diana says the 'Rock On' star is a complete professional, who always came well-prepared on the sets with his lines.
"There was never a moment where he had forgotten his lines or dialogues. There are actors who learn or do things on the sets, while Farhan came prepared. All these things help you as a co-actor," she says.
The actor plays an NGO worker Gayatri Kashyap.
Talking about her role, Diana says, "I sat with Ranjit Tiwari (director) as he has lived with the story and he exactly knows what he wants from a character.
"I discuss things with him. It helps you get more direction. I do a lot of reading. I also drew the nuances of my character from my real-life experiences."
Also featuring Gippy Grewal, Deepak Dobriyal, Ronit Roy, Ravi Kishan and Rajesh Sharma in pivotal roles, the film is set to release on September 15.