How to create account and get the ShipStation keys
First of all, create an account on shipstation.com. The second step is to login to your account, after that, you will see the following screen:
Go to the Settings page. On the left sidebar menu, you will see the API Settings link. Click it:
Then scroll down to the bottom of the page, there you will find the API Keys for your account:
Copy them, go back to your store, when you have installed ShipStation for nopCommerce and go to Configuration page, paste the keys into proper fields:
After all, it's time to specify the default shipping origin, you can do it in Admin Panel -> Configuration -> Settings -> Shipping settings. Please note it has to be the real address. Save changes and that's all.
Customer during purchase will see for example following shipping methods: