Your reservation is your paid receipt which has a confirmation number included
Did u fill it out online? If so did you pay for it online or did you choose to pay for it at 7-11. You will need your confirmation number which would be sent to you in an email. You can also print the ticket off at home or have them print it off at the station. If you print it at home then you would need to make sure that you have your license with you at all times on your trip because the driver and security will check your ticket and require your drivers license for print at home tickets.
If you mean a seat its first come first serve for the seats. Unless you need a handicap seat then they have those upfront marked off.
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