1) Get a Fedex Account
Sign up for an account here.
2) Get a Production Key
Step-by-step guide here.
At the end of this process you should have these four pieces of information:
- Your Authentication Key
- Your Authentication Password
- Your Account number
- Your Meter number
3) Create a new Shipping Method in your shop
Select Administration > Shipping > Shipping Methods in the menu bar.
Click (+) to add a new shipping method
Click the radio button for Realtime in the Rate calculation section
Select a FedEx shipping service from the drop down menu in the Shipping Service section.
Click to add appropriate taxes in the Taxes section if you have chosen to collect and remit taxes
In the Name field at the top of the page enter the same name for the shipping service.
New Tabs will appear for Configure and Shipping Charges
In the Configure tab enter the four pieces of account information you obtained (as listed above).
Check the Test mode checkbox.
To confirm that you are connected:
Return to the General tab and scroll down to the Shipping service. Enter a Test weight value ("1" is fine) and click the Test button. A window will pop up that will show a pickup and deliver destination and in the lower left there should be a shipping cost displayed if you're connected.