What is the first step when starting a credit card tab in a bar?

The first step when starting a credit card tab in a bar is to take the credit card and ID. This is crucial as it verifies the identity of the customer and ensures that the credit card is valid. By requesting both the credit card and ID, bartenders can prevent issues such as fraud and unauthorized transactions.

Taking the customer's preferred drink or finding out who is on the tab are actions that can be addressed after verifying the payment method and identification. Preauthorizing the credit card is also important, as it ensures that there are sufficient funds available, but this typically occurs after the initial verification process is completed. Thus, collecting the credit card and ID establishes a secure foundation for the tab before proceeding with any additional steps.