Aamir Khan believes he is not a natural actor and unlike others has to work his way through a performance to reach the perfect pitch.

The actor says he has a sense of what a good performance entails but it takes him a while to embody the character.

"When I see actors like Naseer (Naseeruddin Shah), Om Puri Ji, Raghubir Yadav, Dilip Kumar Sahab, Amitabh Bachchan Ji and Zaira Wasim, I feel they are a powerhouse. When they give their shot, there is so much belief in them and it comes out very naturally and effortlessly.

"I don't feel that I have that gift. I feel I have to work myself up to that level, it will take a bit of effort to reach that level," Aamir said in a group interview.

The actor, who has completed 30 years in the film industry, says he fights through his doubts and does not mind going through multiple rehearsals if it can better the performance.

Citing the example of "Dangal", Aamir said it took Wasim just a week to pick up the Haryanavi accent, whereas he struggled for four months to learn it.

"I am not a natural (actor). When I start my first reading I feel I am very bad, like when the reading of 'Lagaan' was happening I was like director Ashutosh Gowariker shouldn't drop me as other actors like Raghubir Ji are doing good. My first reading is always pathetic and I start working on it."

But the 53-year-old star believes his biggest strength lies in the fact that he is "not scared to fail".

"I don't mind doing bad rehearsals, again and again, to finally discover where I am supposed to pitch. I have a good sense of performance. Everyone is not a born actor but in my case, I can sense what a good performance is and I work my way there."

Aamir explained his process of acting, saying the performance becomes richer when it is "layered".

"Often how we behave is not how we are feeling. In a performance, if I show I am hurt so that will be a superficial level of performance, the other way is 'I am hurt but I don't show it and you realise it.

"Acting is like layers... I feel my strength lies in my ability to understand that this character is going through a phase and how many layers I need to add to make it look good."

The actor says he would not call himself a method actor as he has not studied acting.

"I have my own method, my own way to finally arrive at what I am now."

Besides acting, a lot of young actors today focus on taking dance and action classes before entering in the movies and Aamir says these skills are important to enhance the overall performance.

"All this is very much part of getting ready to be an actor. Perhaps learning dancing, singing, fight or horse riding or anything is just a skill which if you have acquired in your training, it will come in good help."

He says he needs time to rehearse, especially learn his lines beforehand.

"Sanjay Dutt has a photographic memory. You give him three pages, and he will look at them and keep the paper and will be ready. I don't have a photographic memory, I take time.

"I do rehearsals for three to four months before a film (shoot). I rehearse with the director, then I do rehearsals alone. That's when I memorise my lines so that when I am on the set, I'll be ready. It should be your lines and not the writer's line. I write lines as well."

After working for 30 years, Aamir says it feels like yesterday he entered the industry.

"... When I look back, (I think) good quality performances ended up building a goodwill for my overtime. When you are consistent, only then you are able to build faith.

"I cannot claim I tried to do that but I did try to satisfy myself as a creative person and that ending up in building trust between me and my audience."