How do you say sit down in cat language?

I'm curious, how would one go about communicating the instruction "sit down" to a feline friend in a way that they would understand? Is there a specific vocalization, body language, or gesture that cats naturally associate with this action? Or is it more of a matter of training and conditioning through repeated exposure and positive reinforcement? It's fascinating to think about the complexities of cross-species communication and the ways in which we might be able to bridge that gap.