facing issue in routes

I am using rail 4.2 and ruby 2.2.0p0, I need to submit form which
belongs to user table, once the user authenticate and for authentication
I am using devise, Do I need to create user controller and view manually
or

I have created two directory named as my_devise one under controllers
and other under views. I followed this for the approach which I took. I
am getting "uninitalized constant MyDeviseController" error.Here is the
list of files which I modified.

my_devise/registrations_controller.rb

class MyDevise::RegistrationsController <
Devise::RegistrationsController

def update
    @user = current_user
    if @user.update_attributes(user_params)
      # Handle a successful update.
    else
      redirect_to 'my_devise/registrations'
    end
  end

  private

    def user_params
      params.require(:user).permit(:title, :font, :description,
                                   :bgcolor)
    end

end
my_devise/registration.html.erb

<%= form_for :user, @user, :url => url_for(:controller =>
'registrations', :action => 'update') do |u|%>
<br >
<p>
    <%= u.label :title %><br>
    <%= u.text_field :title %>
  </p>

  <p>
    <%= u.label :description %><br>
    <%= u.text_field :description %>
  </p>

  <p> <%= u.label :back_ground_color %><br>
    <select name="bgcolor" id="bgcolor">
        <option value="#FF3300">Orange</option>
        <option value="#00FF00">Green</option>
        <option value="#0000FF">Blue</option>
        <option value="#FF0066">Pink</option>
        <option value="#FFFF00">Yellow</option>
        <option value="#FFFFFF">White</option>
    </select>
  </p>

  <p>
    <%= u.label :font %><br>
    <select name="font" id="font">
        <option value="Times New Roman">Times new Roman</option>
        <option value="Verdana">Verdana</option>
        <option value="Arial">Arial</option>
        <option value="sans-serif">serif</option>
    </select>
  </p>

<br >
  <p>
    <%= u.submit %>
  </p>
  <hr >
  <div style="background: #{current_user.bg_color};"></div>
  <div style="background-color:#{current_user.font.nil? ? '#FFFFFF' :
current_user.font}">
    This is the changes made in background
  </div>

<div style="background-color:#{current_user.bgcolor.nil? ? '#FFFFFF' :
current_user.bgcolor}">

  </div>

<% end %>

routes.rb

devise_for :users, :controllers => {:registrations =>
"my_devise/registrations"}
  devise_scope :user do
    authenticated :user do
      root :to => 'my_devise#registration', as: :authenticated_root
    end
    unauthenticated :user do
      root :to => 'devise/registrations#new', as: :unauthenticated_root
    end
  end
schema.rb

ActiveRecord::Schema.define(version: 20150420060137) do

  create_table "users", force: :cascade do |t|
    t.string "email", default: "", null: false
    t.string "encrypted_password", default: "", null: false
    t.string "reset_password_token"
    t.datetime "reset_password_sent_at"
    t.datetime "remember_created_at"
    t.integer "sign_in_count", default: 0, null: false
    t.datetime "current_sign_in_at"
    t.datetime "last_sign_in_at"
    t.string "current_sign_in_ip"
    t.string "last_sign_in_ip"
    t.datetime "created_at"
    t.datetime "updated_at"
    t.text "title"
    t.text "font"
    t.string "bgcolor"
    t.text "description"
  end

I am using rail 4.2 and ruby 2.2.0p0, I need to submit form which
belongs to user table, once the user authenticate and for authentication
I am using devise, Do I need to create user controller and view manually
or

I have created two directory named as my_devise one under controllers
and other under views. I followed this for the approach which I took. I
am getting "uninitalized constant MyDeviseController" error.Here is the
list of files which I modified.

Post the complete error message and tell us which line of code it refers to.

Colin