There are many intriguing aspects to this simple, straightforward question. For example, I want to talk about the notion of “calling” ... and about a call from GOD. But I think the heart of the question is how do you KNOW? So let me start there.
The yeses I'm thinking of are more of the yeses into a new moment. Maybe it's the yes to take a new job that will take us in a new direction. Or maybe it's the yes to a relationship that seems to go against our prior assumptions. It might even be the yes to throw caution to the wind and try a new route home from work!