You ask before you do things, and you use your prior relationship with this person to determine how to act around them. It's the same thing you do with non-sexual advances, too. Like, you generally have to be really close friends with a person before they'll be cool with you pushing them around or otherwise touching them; and if you aren't close friends with a person, then you reasonably just don't do this kind of behavior, because it's risky and you know it's unlikely to be perceived well. Or you might talk shit to your friend as a joke, but you wouldn't do that to say.... some random dude, because you haven't established that kind of relationship with him yet, and you have no idea how he is going to respond to it. You only reserve these kinds of behaviors for people with whom you have established an appropriate relationship.

This isn't confusing. These are literally the same exact kind of interactions that we all have on a daily basis. The only thing that's making it confusing is that you feel entitled to make advances on any woman you find attractive, where you don't with other kinds of social interactions. Well I'm sorry, but you're not.