The lady raises her right hand to meet the man's left. Everything else, including the option of using contact, is determined relative to the positions of their joined hands. He could for example bring her in to a position short of contact and establish the connection of his right wrist, or her could bring her in to light contact and then establish it. Likewise, she has the option of inserting a slight extra space between her body and her right hand, which will show up between her body and his.
The lady's left hand will tend to find it's position last. It is a very delicate connection, not a grip except as a signal in emergencies or to re-establish her personal space if a social partner is presumptious.