Go to StarTrekOnline (Link to will be given upon purchase)
Log into your account or sign up for free
Click the gear icon at the top right of the Arc Client
Select "Activate a Product" and enter your code
Launch the game and complete the Tutorial
Claim the item from the CStore in the "items" tab
Note: Gaming code will be only valid till 12/31/2020, and can only be used within United States