Despite what this feature sounds like, it's not what you think. Archiving a page isn't really storing it away, it's a performance enhancing feature that makes publishing go faster.
When a page is archived, it continues to display like any other page. The difference is when it's archived, the page does not get published when you click Publish Website. Think of it as something you do to a page that you are done editing and don't plan to update any time soon.
So, how do you archive a page? Follow these steps:
1) Click Properties on the Page Settings dropdown
2) Check the Archive Page checkbox
3) Click Save
If you need to edit an archived page, just make your edits as usual and publish it from the Page Manager. This over-rides the archive setting.