The easiest way is to go to your Dashboard and then:
Appearance >> Menus
Now somewhere in the middle you will see something like this:
http://tinyurl.com/9elhk9r
All you need to do is to drag the Menu Items above or below to re-order them. For example, I have dragged Test03 above Test02 and this is reflected accordingly in the Menus.
I tried that and this is the problem:
The current theme does not natively support menus, but you can use the “Custom Menu” widget to add any menus you create here to the theme’s sidebar.
What’s the next easiest way, or is there something I can do to force the Greyzed theme to use the method you suggested?