Nop2.0 : add a viewer

Hi all,
I want to add a new menu "note" under "My account"

what I have done are:

1. add a new viewer
Presentation\Nop.Web\Views\Customer\Note.cshtml
2. adda new module
Presentation\Nop.Web\Models\Customer\CustomerNoteListModel.cs
3. modify the customercontroller.cs

[NopHttpsRequirement(SslRequirement.Yes)]
        public ActionResult MyAccount()
        {
            return RedirectToAction("note");
        }

        #region Note
        [NopHttpsRequirement(SslRequirement.Yes)]
        public ActionResult Note()
        {
            if (!IsCurrentUserRegistered())
                return new HttpUnauthorizedResult();

            var customer = _workContext.CurrentCustomer;

            var model = new CustomerNoteListModel();
            PrepareCustomerNoteListModel(model, customer, false);

            return View(model);
        }

4. run the debugging
   I got an error in Presentation\Nop.Web\Views\Customer\MyAccountNavigation.cshtml

<div class="listbox">
        <ul>
           @if (!Model.HideNote)
            {
                <li><a href="@Url.Action("note", "customer")" class="@if (Model.SelectedTab == CustomerNavigationEnum.Note)
                                                                             {<text>active</text>}
                                                                             else
                                                                             {<text>inactive</text>}">@T("Account.CustomerNote")</a></li>
            }            @if (!Model.HideInfo)
            {
                <li><a href="@Url.Action("info", "customer")" class="@if (Model.SelectedTab == CustomerNavigationEnum.Info)
                                                                             {<text>active</text>}
                                                                             else
                                                                             {<text>inactive</text>}">@T("Account.CustomerInfo")</a></li>
            }

Italic part is which I added, error said the Model is null.
object reference not set to an instance of an object.
who can tell me how to instance the "Model".
what is missing somewhere? thanks in advance.