Saif, who is the son of actress Sharmila Tagore and late Indian cricket legend Mansur Ali Khan Pataudi, has come a long way as an actor.
"It's not easy to experiment and I think I can do more than one title role with confidence, so I was enjoying that. I took a bit long to learn my craft, but it's an actor's duty to entertain people. So this film is a commercial comedy," said Saif who started his career with duds like Aashik Aawara (1993) and Parampara (1992).
"An inexperienced actor couldn't have worked in the film. Because if you can't perform, it shows on the screen. I couldn't have done this role 10 years back," Saif, who played a double role in the 1997 film Hameshaa, told reporters in a group interview.
From Main Khiladi Tu Anari to Dil Chahta Hai, from Hum Tum to Kal Ho Naa Ho - the 43-year-old has proven his mettle in comedy at every juncture of his career.
And now he literally lets his hair down for Humshakals and will be seen in three different looks - a billionaire, a childish man and a woman.
It is not only Saif, but even co-actors Riteish Deshmukh and Ram Kapoor have cross-dressed for their respective roles in the movie. "We all were trying, but Riteish looked amazing," he said. "But no competition", he clarified.
"I didn't mind looking bad because I feel it's okay for a guy not to look elegant as a woman but little muscles with a bikini look funny. I was working out more because it should be like a boy trying to look like a girl. I have worn a nylon swimming costume," he said.
Everything was fine, but for Saif "It's difficult to dance in heels. It's not easy."
Humshakals is Saif's first film with director Sajid Khan and the actor describes the latter as an encyclopaedia on movies.
"Sajid is great fun. It was wonderful working with him - he is either laughing or not happy at all. He laughs a lot and he laughs more than anyone else, which is a nice thing. He doesn't take himself seriously.
"It was very tiring because normal things don't interest Sajid. He is an encyclopaedia on films. He feels his safest genre with the audience is comedy and this (Humshakals) is his type of comedy. So far it's looking positive," he said.
Humshakals, which releases on Friday, also features Tamannaah Bhatia, Esha Gupta and Bipasha Basu in the lead roles.
This is Saif's first release of this year and he is looking forward to the film as his much-talked about Bullett Raja with director Tigmanshu Dhulia didn't work well at the box office.
Talking about box office debacle of Bullett Raja, Saif said: "It was a Tigmanshu Dhulia kind of film. He was hoping that if he would take me, the numbers will change, but I think people know what to expect from a film."
According to Saif, producers and publicity plans play a key role in a film's success. "Producers are very important, and I think Sajid Khan is producing Humshakals and he is very driven. See the way he has taken control of the publicity - that's the most important thing. They know how to release the film. It's not just the money. Rahul Mitra (producer of 'Bullett Raja') is a nice guy but he didn't know how to do it," said Saif.