If you want to replace the default DNN navigation with NavXP, please follow these simple steps:
1.Go to Portals_default\Skins\yourskin;
2.Open the .ascx template where you want to add NavXP;
3.In the header, add this line:

<%@ Register TagPrefix="DnnSharp" TagName="NavXp" Src="~/DesktopModules/DnnSharp/NavXp/Main.ascx" %>

4.Replace the default “navbar” div content with this:

<div class="navbar"> <DnnSharp:NavXp runat = "server" id = "avtMenuTop" /> </div>

5.Clear Cache if the menu doesn’t appear from the first refresh.
6.To make sure that the menu is loaded from NavXP, right-click on logo and Click “Inspect”. When the Console opens, scroll up few lines and there should be a div that looks like this:

<div class="navxp...">

7.The menu Id can be changed