Sebastian Stan didn’t "get sleep" during his portrayal of Donald Trump in ‘The Apprentice’.

The 42-year-old actor stars opposite Jeremy Strong and Maria Bakalova as the controversial former US president in the upcoming drama, and has now revealed he had several restless nights spent perfecting his take on the maverick politician.

During an appearance on ‘Today’, he said: "Well, [you] try to get sleep, which I didn’t. There’s a lot of research out there, there’s a lot of footage and documentaries. It’s pretty much been very well documented, his sort of rise into what we see today.

"And to me, it’s like playing an instrument. You sit at the piano, you get better at it with practice, and eventually you can just kinda do it in your sleep."

In order to ensure his performance as the businessman was as accurate as possible, Stan studied roughly 700 video clips of Trump spanning 50 years.

The Marvel star told Variety: "I had 130 videos on his physicality on my phone. And 562 videos that I had pulled with pictures from different time periods - from the 70s all the way to today - so I could pull out his speech patterns and try to improvise like him."

After studying the way Trump speaks, Sebastian realised he needed to change the way he moved his lips.

He explained: "I started to realise that I needed to start speaking with my lips in a different way. A lot of that came from the consonants. If I’m talking, I’m moving forward ... The consonants naturally forced your lips forward."

The picture’s director Ali Abbasi added the ‘Thunderbolts*’ actor had to find the right balance when playing the presidential candidate so it didn’t stray into the realms of impersonation.

He said: "If he did 10 per cent more of what he did, it would become ‘Saturday Night Live'. If he did 10 per cent less, then he’s not conjuring that person.

"But here’s the thing about Sebastian: He’s very inspired by reality, by research. And that’s also the way I work; if you want to go to strange places, you need to get your baseline reality covered very well."

‘The Apprentice’ - which will be released on 18 October - follows Trump’s rise to power in the 1980s during his early years as a real estate businessman in New York.