How do I redeem a code in Rocket League?

Some items can be placed in your inventory by entering your redemption code through the in-game menu. To do this, follow the below steps: 

1. Launch Rocket League.
2. Select Settings from the menu.
3. Select Extras. 
4. Select Redeem Code.
5. Type in the in-game redemption code
   All codes need to be entered exactly as they are printed. Make sure to include the dashes (-) and avoid adding extra spaces at the beginning or the end of the code 
6. Select OK.