Olivia Colman had to have lessons in walking like the Queen – after being told her normal gait looked “a bit like a farmer”.
And The Crown actress also had voice coaching when she realised a “general posh accent” would not cut it.
Colman, 45, takes over from Claire Foy in series three of the hit Netflix drama.
The star revealed that playing Elizabeth II in middle age had not been as easy as she first imagined.
She said: “I can't just sit like me, I have to sit like her, and look like pictures of her.
“They have been teaching me how to walk – I walk a bit like a farmer, one of the directors said.”
In terms of speaking like the Queen, she told Harper’s Bazaar: “I thought that general posh would do it, but apparently not. If you’re saying ‘yes’, you say ‘ears’. It’s fun to do. Very hard to stop. Ears.”
Colman – who won an Oscar earlier this year for her role as Queen Anne in The Favourite – also says she is being paid at least as much as her co-star Tobias Menzies, who replaces Matt Smith as Prince Philip.
She said: “I bloody well hope so! It’s not called Philip, it’s The Crown.”
Olivia is also concerned that the Me Too movement might run out of steam. “I hope that people don’t get bored of it,” she said.
The Crown series three is available on Netflix from November 17
