Create a new perfil inside a persons _controller - ruby-on-rails-3

Question

I'm in rails 3.2.2
I'm trying to create a new perfil inside a persons_controller
Models symplify:
class Person < ActiveRecord::Base
belongs_to :perfil, :foreign_key=>'perfil_id'
class Perfil < ActiveRecord::Base
has_one :person
I created ad_perfil inside persons_controller
def ad_perfil
#person = Person.find(params[:id])
#perfil = Perfil.new
end
and I supused 2 ways:
1) using f.submit
ad_perfil.html.erb:
<%= #person.nombre %>
<%= form_for(#perfil) do |f| %>
<div class="field">
<%= f.label :nombre %><br />
<%= f.text_field :nombre %>
</div>
<%= f.submit %>
<% end %>
this redirect me to create to perfils_controller and there I can't get #persona:
def create
#perfil = Perfil.new(params[:perfil])
#person = Person.find(params[:id])
respond_to do |format|
if #perfil.save
format.html { redirect_to #perfil, notice: 'Perfil was successfully created.' }
format.json { render json: #perfil, status: :created, location: #perfil }
#person.perfil_id = #perfil.id
#person.save
2) I created a new def in persons_controller:
def new_perf
#perfil = Perfil.new(params[:perfil])
#person = Person.find(params[:id])
if #perfil.save
#person.perfil = #perfil
#person.update_attributes(params[:person])
redirect_to #person
end
end
and I tryed change f.submit for:
<td><%= link_to 'New Perfil', :action => "new_perf", :id=> #person.id %></td>
and it created a new perfil without any field and of course don save perfil.id inside #person.perfil_id.
Is possible that I'm trying? Is there any other methods? I guess that will be more easy puting perfil.person_id instead person.perfil_id but I want access to person.perfil later.
I hope you understand me, and maybe I don't understand "submit" very well. any suggestions? thanks!