Painting concrete, which color, which method?

I have no experience with concrete paint so far, hence the question. Simply painting over other surfaces can, as is well known, sometimes not lead to the desired result, and I just wanted to make sure how it behaves when painting over already painted concrete. After all, it has different properties than other surfaces. And since it is not, for example, a ceiling, which naturally comes into contact with shoes or the like less often than our stairs do, it really has to be durable...

If you have had good experiences with simply painting over with concrete paint without pretreatment, that is enough for me. Thank you very much for that!

Best regards, Sebastian

We also did it back then with regular concrete paint. It worked great.