After you collect your bags, walk out the doors and across the street to the parking garage. Follow the signs to
Alamo section. Look for the aisle that corresponds to your rental type, get in any car there and drive to the exit booth. Show them your skip the counter var code, license, credit card I think? Sometimes when you get to the garage their is an Alamo employee standing around to point you to the correct aisle, but they are clearly marked.