class User < ApplicationRecord
  # Include default devise modules. Others available are:
  # :confirmable, :lockable, :timeoutable and :omniauthable
  devise :database_authenticatable, :registerable,
         :recoverable, :rememberable, :trackable, :validatable

  has_one :profile, dependent: :destroy
  after_create :build_profile
end

class RegistrationsController < Devise::RegistrationsController
  protected

  def after_sign_up_path_for(resource)
    edit_profile_path(current_user)
  end

end

class Profile < ApplicationRecord
  belongs_to :user
  ...
  validates :name, presence: true
end

def set_profile
  @profile = Profile.friendly.find(params[:id])
end

Couldn't find Profile with 'id'=6

def set_profile
  @profile = Profile.friendly.find(params[:id])
end