Spring Awakening was my first job out of drama school.

I won an Olivier Award for it – it was a genuinely surreal time in my life. It’s something I would aspire to achieve in 10 years, not when I’d just moved from the Welsh valleys and had been itching to get out of drama school. [Aneurin went to Royal Welsh College of Music & Drama.]

Drama school gives you an amazing amount of theatre knowledge. If you want to be a stage actor I don’t think you can without training; some do, but it’s a very low percentage. I knew from 14 that I wanted to go – mainly to get an agent, because I had already been acting for a few years, though I was very rough.

You shouldn’t live in fear of your agent. It’s a business, a partnership – you need to get on. Look in detail at how long agents have had clients for and who they developed – that’s the important thing. You want someone that builds careers. Ultimately, though, when you step into that casting room it’s all down to you. A great agent doesn’t mean your career is secure.

I just played the title role in Mariah Mundi and the Midas Box. I did lots of fighting and falling – I grew up climbing trees and I’ve been swordfighting since I was 11, so that was my training. I knew I wanted to be an actor and wanted to be ready to do anything asked of me.

When I played David Bailey [in We’ll Take Manhattan, pictured], I was interested in everything that had happened to him up until the point when the film started – things that the public don’t know, and in little things like the fact he looks through the camera lens with his left eye. Nobody else would notice, but it was my job to.

I change my preparation for each job. Ironclad was set in 1215 and based upon true facts about the Magna Carta. My character was made up, so there wasn’t much research I could do, except for knowing the period. With Citadel, where I played a young single father suffering from agoraphobia, I spent a lot of time with sufferers – it was very intense and emotional, but I had to make sure I was as convincing as possible.

It all depends on the job. Research is important – sometimes directors will suddenly say, “Let’s roll a take and do an improvisation.” If that happens and you haven’t done your research, you’ve got no idea how you’re supposed to react in that moment. Always do more than needed, then you can’t fail.

I worked with Derek Jacobi on Ironclad. You can’t be intimidated by people you respect – if they raise the bar, you’ve got to try and raise it above them. Sit back and listen ­– let them give you a masterclass without them even knowing it. Derek spoke about becoming part of the first company at the National Theatre, with Mr Olivier himself. I asked who the one person he wished he could have worked with was, and he said, “Darling, I’ve worked with them all”. And of course he has!

Aspire to be the best, seize every opportunity and perform to the highest standards you can and at some point you’ll get your break, but never take it easy or for granted. Always be completely yourself. There’s a lot of bitching in the industry – stay out of it, be respectful to others and set goals.

For more articles, jobs and opportunities, visit the Performing Arts hub.