4. Follow Airline Best Practices for Check-In
Watch the gate agent adhere the baggage-check tag to your suitcase. Confirm (with the agent if need be) that both it and your claim check have the proper three-letter destination-airport code. Take a photo of your baggage-claim ticket, in case you misplace it. To be extra careful, use a baggage-tagging service, which, for a fee, supplies tags with unique serial numbers linked to you in an online database. Finally, while in line at security, make a mental list of all the things you'll put in the bins or on the conveyor belt, so you're less likely to forget something on the other side.
5. Deal With Lost Luggage Immediately
Remember — don't panic. First, look around: your bags might be near your carousel or on or near another one. If not, go to the airline representative counter with your baggage claim, boarding pass and luggage description/photo. Breathe deeply, stay calm and be polite. Some airlines can tell you where your bag is (or where they think it is). It might even be on the next flight from your point of origin, in which case you might want to wait. Regardless, do not leave the airport before filling out a lost-luggage report and getting (1) a copy of the report; (2) an airline contact name and number so you can follow up; and (3) details, in writing, of how to file a claim and when the airline will reimburse you — for essentials you purchase (save receipts) until your lost luggage is found or for all items if it's lost for good.
6. Follow Up
On check-in, inform hotel staff that the airline has lost your luggage and will deliver it later. A concierge might help with follow-up calls to the airline; regardless, be sure that there's follow up. Also, some hotels provide sundries to tide you over. If, in the end, you feel the airline treated you unfairly, file a complaint with the Aviation Consumer Protection Division. And, going forward, consider flying only with carry-on luggage.
Also of interest: What you should NOT pack for your trip.