user.rb

class User < ActiveRecord::Base
  def welcome
    send_welcome_email(self)
    enable_welcome_tour(self)
    enable_welcome_promotion(self)
  end

  private

  def send_welcome_email(user)
    WelcomeMailer.welcome(user).deliver
  end

  def enable_welcome_tour(user)
    user.welcome_tour = true
    user.save
  end

  def enable_welcome_promotion(user)
    promo = Promotion.new(name: "Thanks for joining!")
    promo.set_redeemer(user)
  end
end