Flying to a destination abroad for the first time can cause feelings of excitement and trepidation, as many travelers are concerned with flight comfort, logistics and getting through customs at their destination. With a few tips, even novice world travelers can have a restful flight, sail through customs and get on with their trip.
Sleep and Eat on Destination Time
Many airlines try to help travelers adjust to a different time zone by closing the shades and dimming the cabin lights for sleep even while the mid-afternoon sun is shining at the departure city. Taking advantage of sleep during this time helps travelers prevent extreme jet lag and exhaustion upon landing. If sleep is elusive, be courteous of other travelers by staying quiet during this time. Bring snacks or enjoy light meals about the time that the people at your destination would be settling down to a meal. This also will help with schedule adjustment while you're abroad.
Make the Seat a Comfort Zone
On long flights, a business suit or pair high heel shoes is not conducive to comfort. Change as the plane approaches your destination or at the destination's airport, but wear comfortable clothes and thick socks for most of the flight. Be sure to bring lip balm, unscented hand lotion, earphones, earplugs if necessary and any other item that will help you relax or sleep. An eye mask can block light and allow for deeper sleep, and a neck pillow will provide comfort and support.
If the flight is a long one, make sure to get up and move around regularly. Airline staff usually expect to see passengers walking the aisles on long flights, so don't feel awkward with cruising around the cabin and stretching out of the way of other travelers; just avoid restricted areas. Stretching in yours seat also can be effective in reducing stiffness. Try small leg circles, neck rolls or arm stretches.
Prepare for Customs
Preparation for getting through the destination's customs area starts before landing. In the air, most airlines provide travelers with the necessary immigration forms. These forms usually ask for the flight number of the arriving flight, its departure city, which other countries you have recently visited and if you are carrying anything unusual, such as food items or large sums of money. As a general rule, countries try to avoid botanical infestations from foreign fruit and soil, so airline staff may ask that fruit be consumed or thrown away before landing.
Source - http://traveltips.usatoday.com/tips-first-time-fliers-international-flights-40395.html