The tap card machine
Also keep in mind, I believe, in the event u use the MTA bus lines and if you already have a tap card, as you board the bus, just inform the driver that you would like to add $5 or $10, load the cash in and at that point the driver will instruct you to tap ur card and there u go, ur all set. This would be the option if you would ride the bus as well.
At the station. Every station has a machine. Just purchase a tap card.
Every station has a trap card vending machine.
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