Explain to a non-fitness human: How can you tell when someone is on steroids?

[ShyHornyAfreakcan]

Are there visual tells?

Do actors get on steroids for action roles? (Chris Hemsworth for Thor, Michael B Jordan for Killmonger)

I can't tell so I'd appreciate being able to recognize it.

Thanks!

Please share examples of people who are lauded for their bodies but aren't natural so I can feel better about myself, thanks