This blog post is completely copied from Joshua34com. So all credits go to him.

The solution is very simple, why create your own solution when
you can copy it.

But what I was missing in this article is that you need to
change the default WYSIWYG setting. I am doing this always
because it is changing your code. So set your WYSIWYG to be
disabled by defautl. You can do that in System >
Configuration > Content Management

First copy topmenu.phtml from

/app/design/frontend/rwd/default/template/page/html/

Save this file as topmenu.phtml to

/app/design/frontend/YOUR PACKAGE/YOUR THEME/template/page/html/

Edit this file within lines 38-40, paste the
following:

<?php echo $this->getLayout()->createBlock('cms/block')->setBlockId('home-link')->toHtml(); ?>

To create:

<ol class="nav-primary">
<?php echo $this->getLayout()->createBlock('cms/block')->setBlockId('home-link')->toHtml(); ?>
<?php echo $_menu ?>
<?php echo $this->getLayout()->createBlock('cms/block')->setBlockId('post-menu-links')->toHtml(); ?>
</ol>

Save and reupload this file.

Create a CMS > Static Block, named home-link enter the
following into your block (Hide Editor, as needed):

<li class="level0 nav-1 parent"><a href='{{config path="web/unsecure/base_url"}}' title='Home Page' class='level0'>Home</a></li>

Note: I leave all of the class names consistent with 1.9. Feel
free to adjust class names as needed.

Save your new Static Block.

Create a CMS > Static Block, named post-menu-links Enter the
following into your block (Hide Editor, as needed):

<li class="level0 nav-1 parent"><a href="CUSTOMPATH-1.HTML" title="LINK TITLE #1" class="level0">LINKNAME #1</a></li>
<li class="level0 nav-1 parent"><a href="CUSTOMPATH-2.HTML" title="LINK TITLE #2" class="level0">LINKNAME #2</a></li>
<!--  and so on, as needed ...  -->

Save your new Static Block.

Be sure to clear the cache and refresh your browser.