Faith is the one to dominate Xander.

So you've chosen Faith as the one to dominate Xander, now all you have to do is make your choice onto when she dominates him.

Does she dominate him when she first comes to town or how about when she turns evil and joins the mayor. what about when she steals Buffy's body for her own, or how about when she joins the gang for the fight against the first evil.