The first step to make your app js-degradable is to not introducing javascript at all.
In the second step you hook into jQuery.ready() for the document, traverse your DOM dynamically and attach event handlers to them (to links, submit buttons, etc).
If the user doesn’t have js prior to visiting your page, document.ready is not triggered at all (as there’s no javascript support), thus your page will be left as it is (how you designed it in the first step).