In my experience she has never waited for me to ask a question to start the call. She just starts talking with what she's seeing. Very often, that's what's on my mind so I don't have to do more to steer things. If it's not, and I let her go on for a while and she's not getting there, I will ask a broad question like "What do you see with my love life?" or "What do you see with this new job I'm interested in?"
It's my very un-scientific opinion that for me she is most accurate without a question, just with what comes up on her own, so I try to let her go that route for as long as possible. I definitely prefer not to weigh her down with a lot of backstory, and I try to stay focused on big picture if I do ask a question rather than "Will x ask me to this event?" or whatever. Hope that helps!