Hurricane Sandy has made landfall in the U.S., but its effects on air travelers are being felt throughout the globe. Airlines say it will take days for them to resume service to normal levels, so your upcoming flight may be affected.

Here’s what you can do if your flight is canceled:

• Don’t go to the airport.

• To avoid getting stranded at the airport, check your flight’s status early the day you’re flying, and again right before you head to the airport.

• If you’re already at the airport when your flight is canceled, put your legs and fingers to work. Walk over to customer service. While there, dial the customer service number. Odds are you’ll get help over the phone before reaching the front of the line. Still, in the case of Sandy, the best you might do is a cot, like those the Port Authority is promising to supply to stranded travelers.

• You can try asking for assistance via Twitter. Most airlines task employees with monitoring their Twitter feed. However, for this storm, JetBlue has requested that people in need of help call the airline. Other airlines could do the same.

There are also a couple of financial basics to be aware of.

The airlines have waived change fees, typically $150, for flights delayed or canceled due to the storm. But keep in mind that airlines usually only waive this fee once. Be certain you want to change your itinerary before you lock it in. Otherwise, you’ll be out $150 if you have to make a second change. You also might pay more for a difference in the flight’s price.

If you cancel your booking altogether, the airline might offer you a voucher for a future flight. You can ask for cash instead.

Also, the airline isn’t responsible to pay for a hotel room or food if you’re stranded due to weather