Subscriptions are central to Chargify. They tie your Customers to your Products and are responsible for billing and charging on your recurring intervals.
Once a Subscription has been created, it will begin to auto-renew on the period specified by the Product to which it is related. There’s not much you need to do, other than keep tabs on them from time to time looking for Subsriptions that go sour. If you’ve got automated Dunning turned on, keeping up with what going on will be even less of a concern.
Hint: Turn on the Daily status emails in the Notifications tab to stay on top of things. You can go even farther and add yourself as a BCC recipient on every email that goes out to your Customers.