Robert Pattinson: I don't really know how to act

Robert Pattinson doesn't "really know how to act".

The 33-year-old star is one of the most sought-after actors in Hollywood - but Robert has admitted to being unsure of himself on-set, meaning he's taken to punching himself in the face, or twirling around to create dizziness in order prepare for his scenes.

Robert - who also occasionally forces himself to gag prior to shooting a scene - shared: "I don't really know how to act, I kind of wanted to somehow make it real, and one of the ways I've always thought makes that a little bit easier is if you shake up your physical state just before action. You end up walking into a scene having a different ... feeling."

At times, Robert would gag so hard that he'd actually throw up.

He told the Observer newspaper: "I forgot I had a mic on the whole time, so the producers and the director, before every single take of the movie, would get ... It kind of puts everyone else off."

The London-born actor freely admits to being a "catastrophist".

However, Robert feels that in some instances, his pessimistic outlook can be beneficial.

He said: "I'm a catastrophist. I'm always thinking that the worst-case scenario is actually going to happen. So when it does happen, I'm like: 'Gah! OK! I'm prepared!'"

Robert also revealed he's drawn to particular types of on-screen characters.

He explained: "I'm not entirely sure how to play, like, a normal person. I don't think I'm great at subtle.

"I like characters who, when a situation is placed upon them, their decision-making process is incomprehensible. I find it fascinating when people make bad decisions. The humour and the befuddlement."