wizard形式　新規登録　session

前提・実現したいこと

wizard形式で新規登録画面が作りたいです
tebleがuserとaddressの二つあります
registration.hamlで記述したものをuserのtableへsessionを使い保存
address.hamlで記述したものをaddressgのtableへsessionを使い保存
createでデータベースに保存をする

該当のソースコード

class SignupController < ApplicationController

def registration
@user = User.new
end

def address
session[:nickname] = user_params[:nickname]
session[:email] = user_params[:email]
session[:encrypted_password] = user_params[:encrypted_password]
session[:last_name] = user_params[:last_name]
session[:first_name] = user_params[:first_name]
session[:last_name_kana] = user_params[:last_name_kana]
session[:first_name_kana] = user_params[:first_name_kana]
session[:birth_year] = user_params[:birth_year]
session[:birth_month] = user_params[:birth_month]
session[:birth_day] = user_params[:birth_day]
@address = Address.new
end

def create
@user = User.new(
nickname: session[:nickname],
email: session[:email],
encrypted_password: session[:encrypted_password],
last_name: session[:last_name],
first_name: session[:first_name],
last_name_kana: session[:last_name_kana],
first_name_kana: session[:first_name_kana],
birth_year: session[:birth_year],
birth_month: session[:birth_month],
birth_day: session[:birth_day]

)
@address = Address.new(
  post_code: address_params[:post_code],
  prefecture: address_params[:prefecture],
  town: address_params[:town],
  address_num: address_params[:address_num],
  apartment_info: address_params[:apartment_info]
)

if @user.save && @address.save
  session[:id] = @user.id
  @address.merge(user_id: @user.id)
  redirect_to done_signup_index_path
  
else
  render :registration
end

end

def done
sign_in User.find(session[:id]) unless user_signed_in?
end

private
def user_params
params.require(:user).permit(
:nickname,
:email,
:encrypted_password,
:last_name,
:first_name,
:last_name_kana,
:first_name_kana,
:birth_year,
:birth_month,
:birth_day
)
end