The simple answer is however feels most natural to you. But that's vague, so when people aren't sure where to start I usually suggest they try to explain whatever it is that's most at the forefront of their thoughts. Since people tend to only seek out therapy when there's something specific bothering them, they usually have at least one topic like that where the conversation can start and then progress from.
If you mean how in terms of emotion, for some people it helps them to keep some mental distance by explaining their problem like they were just giving a summary of something that happened in a book or the news. Again, usually it just progresses from there.
no subject
If you mean how in terms of emotion, for some people it helps them to keep some mental distance by explaining their problem like they were just giving a summary of something that happened in a book or the news. Again, usually it just progresses from there.