1. First create a user for the app (shipstation) to use when connecting the two systems. To do this, go to System, Web Services, and then choose SOAP/XML-RPC - Users.
2. Click on the Add New User button.
3. Fill in the information for your new user. Make sure to enter "shipstation" as the username, and you will need to create your own API key. You can get this out of your shipstation account. Usually, these are 40-character strings that includes both letters and numbers. Make sure to enter the same thing in both the API key and the API Key Confirmation fields. Please save a copy of API key we will need it if you need support.
4. Once you've done that, simply click on the Save User button.
5. Now login to your ShipStation account.
6. Next, select Selling Channels and then Store Setup from the sidebar on the left.
7. Then, click on the Connect a Store or Marketplace button and select "Magento". Our system is a derivative of Magento.
8. Enter the username, API key you copied, and the URL for your store and then test the connection.
9. If you use any custom statuses, you'll need to change them while you're setting up your store in ShipStation. Also, at this point you can add your Warehouse Location Attribute and select when Magento will invoice.
10. Your almost done. Click Finish to fill in the rest of the information for the store.