It’s easy! If your app is ready and you want to be among those developers who get to submit to the store early, simply attend one of the 100s of free Application Excellence Labs that DPE and Windows are holding around the world.
Follow these steps to get invited to an App Excellence lab:
For more detail, read Jaime Rodriguez’s blog post here “Wanted!! Great Windows 8 Metro style apps ”.
You can download Windows 8 Consumer Preview and developer tools and SDK here.