Navigate to the Keys page in the desktop application.
Click "Purchase Keys" on the Keys page.
Enter your desired quantity.
The recommended max quantity per transaction is 100 keys. Purchasing more than 100 keys in a single transaction will likely fail due to gas limits on Arbitrum One. There is no limit to the number of Keys per wallet.
Enter a promo code (if you have one).
Click "Confirm Purchase". This will pop you out to a web browser.
Complete the remaining steps using the guide below: