You can use WPF's excellent Navigation panel just like as browser forward and backward button.You can navigate within your forms easily and you need not do much code for that.
You need to just call NavigationWindow like..
<NavigationWindow x:Class="SGS.MainWindow2"
xmlns="http://schemas.microsoft.com/winfx/2006/xaml/presentation"
xmlns:x="http://schemas.microsoft.com/winfx/2006/xaml"
Title="SGS" Height="359" Width="587" Source="choicePage.xaml" WindowState="Maximized">
</NavigationWindow>
Where Source means that form what you need to show at startup your program.
See an example..
http://paulstovell.com/blog/wpf-navigation[
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