Newbie question: one to one relationships in ROR

A newbie to ROR, I have come to my first problem. We have two tables
lets call them toys and trucks that have a one to one relationship. Now
toys has_one truck and truck belongs_to toy. I have created the basic
scaffold for both tables. But in order to create a new truck the user
must first create a toy. What I am trying to do is create on page where
the user can enter the information that a toy needs and the information
that a truck needs and create a new record in the respective tables with
the truck’s FK linking to the toys table. Any pointers would be
helpful. Thanks!