From the Admin Dashboard on the left of the screen, navigate to the Expenses tab and click "Manage cards".

Click the blue "Get Started" button. You'll see "Terms of Service agreement" pop up. From there, click the blue "Register account" at the right bottom corner of the pop-up.

Once your account is registered, you can manage limits, track spending, and download spending statements for your Playground card.

Check out these specific articles on automatically tracking expenses with Playground: