If you only have one store, then it's pretty easy to manage all of the orders from within WooCommerce. If you have multiple WooCommerce stores or you sell items on EBay or some other e-commerce platform, then it's worth exporting the orders out of all of the stores into one place where you can manage them. One of the best tools to do this is ShipStation.
You must install and activate the free ShipStation plugin from WooThemes.com.
ShipStation only works when it can talk to your site, so it must be accessible online. You can't use a test site that's running on your local machine.
Getting your store to export orders is pretty painless. You need to copy a key from WooCommerce into your ShipStation account. The first part of this is getting that key from WooCommerce.
Now you'll have to set up your ShipStation account.
When you start using ShipStation, you'll want to set up a few shipping providers to get quotes through ShipStation and create shipping labels.
The default settings for this plugin are pretty useful. By default, any processing— completed, on-hold, or cancelled orders—are sent to ShipStation. You can manage those orders in ShipStation, and once they've been marked as completed, they'll also be marked as completed in WooCommerce.