I've never been out of my home country, the USA; but have flown around the country enough to offer some advice that may help the less experienced air traveler save some valuable time and some money. Reserving your travel arrangements
The first step to traveling, ideally, is to book your travel arrangements (rental car, hotel, flight.) The Internet is the best tool to use in completing this step.
Why is the Internet the best tool? 1. Because you can buy directly from the service providers; cutting out the travel agency commission; 2. One hour spent online will provide you with more information than you could gather by spending several hours on the phone; 3. Web sites are available 24 hours a day, 7 days a week; and won't become annoyed with you even if you come back to check prices every 15 minutes.
I could post links here to all the sites I mention; but you can find them almost as quickly by using a search engine, so I'm not going to post links. All you need is Google, Yahoo, MSN/Live, or your favorite search engine.
The first thing you should do is compare prices.
What I do first is check Travelocity, Expedia, and Orbitz. I know what city I'm going to so that isn't a variable, but I'll select 2 or 3 different hotels, and write down the pricing offered by each of these 3 web sites for each hotel. So I'll have a list of 6 or 9 or maybe 12 prices for my total vacation package. If you're going to rent a car, don't forget to include that in your package price checks. Hotwire is another travel aggregator you may want to check. I think checking three aggregators is enough but if you want to be more thorough, check all four.
If you're undecided on a hotel, pay attention to the star ratings as you're checking rates. The travel aggregator sites all assign a rating of one star to five stars for each property. These ratings are pretty accurate. You probably won't want to stay at a one star or two star property.
Next, I visit the web sites for individual airlines, rental car agencies (such as Hertz, Budget, Avis, Dollar, Thrifty) and hotels; and again write down prices for each.
Third, I'll visit Travelaxe and see if their hotel prices are any lower than the hotels' own web sites. (Travelaxe searches multiple web sites for hotel prices.)
This sounds like a lot of Internet surfing but actually only takes one to two hours. What you'll now have in front of you are A) a list of total package prices, and B) individual prices for flight, hotel, and rental car.
You'll quickly see if it's less expensive to book your travel as a package or to make your reservations directly through the airline, hotel, and rental car web sites.
My experience has been that the package prices are usually higher than booking each service separately. But sometimes you do come across a fantastic package deal (in December 2007, Wynn Las Vegas was offering a huge discount through the aggregator sites... a two night stay was about $400 less expensive as a package than by booking separately.)
Flight times may also figure into your decision. If Orbitz is $50 cheaper than booking separately but you have to take a 2:00 a.m. flight, you may not want to bother with the $50 savings and instead book a flight at a more reasonable hour.
You should conduct this research about a month before your travel dates. As flights and hotels fill up, their prices may also go up. On the other hand, a flight or hotel that isn't getting any bookings for certain dates may lower the prices for those dates as they approach. Airlines, however, rarely offer good rates less than 14 days in advance; so 15 days should be your absolute minimum cutoff before you make your final decisions and book the travel.
Packing
You've paid for your trip; so all that's left to do before your departure date is to pack for your trip.
I strongly recommend restricting yourself to one carry-on sized bag. The long lines at the baggage check counters, the possibility of lost or stolen luggage, and the waiting at the carousel to pick up your luggage, add too much of an annoyance factor to be worth participating in unless absolutely necessary.
Roll your clothing tightly rather than folding it, and you'll fit more in your bag.
Take old worn out clothing that you're about to convert to rags or throw away; and discard them at your hotel instead. This will provide some extra room in your bag for souvenirs to take home with you on the return trip.
Wear, rather than pack, jackets, hats, or coats.
LIQUIDS and GELS are restricted to as many three ounce containers as will fit in a quart sized zip top plastic bag. Get organized in advance and you won't end up being "that jerk who held up the security line because of bottled water" or whatever.
Stick deodorant and Chap Stick are solids, so don't worry about them; they don't need to go into the quart bag.
Cigarette lighters, surprisingly, are allowed in luggage and carry on bags.
Most airlines allow you to carry on one bag and one "personal item" which includes cameras, purses, laptops, and briefcases. Carry on bags generally must be approximately 24 x 16 x 10 inches in size or smaller, but this varies by airline. The exact dimensions will be posted on their web site, so check and make sure you have a bag of the proper size.
24 hours before departure
I think EVERY airline now offers online check-in beginning exactly 24 hours before your scheduled departure time. You can also print out your boarding pass right at home from your inkjet printer. Southwest Airlines assigns passengers a number; the order in which they check in is also the order in which they must board. #1 is first, #2 is second, etc. So if you're flying Southwest, I advise checking in online exactly 24 hours before your flight. For the other airlines, you've already selected your seat from a seat map when you purchased your ticket; so exactly what time you check in is less important. The main advantage to online check in is avoiding a check in line at the airport.
Most airports have self-service electronic kiosks (like ATMs) that let you electronically check in and print your boarding pass. However, there is always a chance that these might be offline when you arrive at the airport. So if you can check in before arriving at the airport you can avoid this possible delay.
If you weren't near a printer when you checked in electronically, you can use one of these kiosks to print your boarding pass. Some airlines let you check in using a cell phone. That's a handy trick for your return flight: check in by cell phone or laptop 24 hours before your return, then print out your boarding pass at the airport.
Departure day
Airport web sites and the media are constantly reminding us to arrive one hour or two hours early. I've found that this is often wasted time.
Quite often, you can get from the airport entrance to your gate within 10 or 15 minutes. Then you've got an hour or two of waiting around.
Each airport has slightly different rules and services available. Some airports let you bypass the long line at the security point if you have a frequent flyer card. Show your card, and you get to use a much shorter "VIP" line. Some airports have the same type of VIP line for first class ticket holders. Check the web sites for your airports in advance to learn which services they offer.
Certain days of the week, times of day, and times of the year are busier than others. Fridays, Sunday evenings and Monday mornings, and a day or two before and after a holiday are often busy times.
You may still want to arrive at the airport an hour or two early to avoid possible traffic delays or other unforeseen holdups; but if you're not traveling at a peak time, 30 to 45 minutes is plenty early enough if you've already printed your boarding pass and you're not checking any baggage.
As you approach the security line, have photo ID and your boarding pass ready to be checked.
Metal
Do not wear any metal. I always leave a little bit of space in my carry on bag for storing my watch, belt, cell phone and keys; which I remove in the airport lobby before going through security. After going through security you can put your belt and watch back on, and put your cell phone and keys in your pockets. And other small metal items like MP3 players and PDAs.
You'll most likely have to take off your shoes before going through security. Even if they contain no metal.
To get through security efficiently, take off your jacket or coat and shoes while you're on line. Your small metal objects (belts, keys, coins, earrings) should already be in your carry on bag. This way you'll get through the metal detector with no delays.
Boarding
Some airlines allow more boarding time than others. Southwest Airlines is probably the worst (or best, depending on your preference) at herding passengers onto flights. Experienced Southwest Airlines travelers are lined up and ready to board before the plane is even at the gate; then quickly hustle on board as soon as arriving passengers have exited the aircraft.
Bags and personal items carried onto the plane must be secured either in overhead storage compartments, or under the seat in front of you. Some rows of seats (bulkhead rows, which are the first rows of seats in first class and the first rows of seats in coach; and emergency exit rows) don't have under seat storage available; so if you're in one of those rows you'll have to store all your stuff in the overhead compartment. While the "fasten seatbelt" signs are lit up, you aren't supposed to be getting up and going into the overhead storage; so if you have small items you want to access during the flight (MP3 player, book, magazine, medication, etc.) keep them in a shirt or jacket pocket.
Airline seats are mostly 17" wide (first class is wider.) This has been a point of embarrassment for some travelers who may be required to buy two seats, because they don't fit in one seat. Weight and health are not as much determining factors as body shape. A professional weight lifter who has zero body fat might be too big for one seat.
If your waist or hips are 42" or larger, you might not fit in one seat. Opt for first class or buy two coach seats if you know you're not going to fit.
Exact seat sizes and more details about seat comfort can be found online:
http://www.seatguru.com/
http://www.sizewise.com/docs/skies.html
The flight booking page on the airline web sites give you the make and model of the plane you'll be flying on.
During the flight
Don't count on the onboard magazines to interest you for more than five minutes. Bring a book, several magazines, MP3 player, or fully charged laptop or portable DVD player to occupy your time and deflect chatterbox seatmates.
You're allowed to bring food on the plane, and beverages purchased in the airport shops that are past the security screening checkpoint. Most flights that are shorter than 3 hours in travel time don't serve meals. You might get a one ounce bag of peanuts or pretzels.
All flights should have a beverage service, however. You can get a free 6 ounce cup of juice, soda, or water; or purchase beer or a mixed hard liquor drink. Bring singles (one dollar bills) if you plan on purchasing drinks, as there isn't any change available to flight attendants at 30,000 feet.
Arrival at the destination airport
You're probably anxious to get to your hotel by now. If you're renting a car, you can speed up the process by having a printout of your car reservation (or at least the confirmation number), credit card, and drivers license ready before you step up to the counter.
Rental car agencies will try to "upsell" you with various insurance options. Most travelers don't need them. If you have your own auto insurance, or a "premium" credit card, this might cover any damage to the rental vehicle. If not, you'll want to purchase the LDW (loss damage waiver) or CDW (collision damage waiver) which covers any accidental damage to the rental vehicle.
Most states require car rental agencies to include the minimum liability insurance required by that state's law with the rental, so don't feel pressured to buy the extra supplemental liability insurance (SLI) either.
If you're not renting a car, you'll probably want to take a taxi from the airport to your hotel. While shuttles can be less expensive, they also take longer since they make many stops (at each passenger's hotel) along the way.
Shuttles also sit there and wait until they fill up enough to make the trip profitable, before they'll leave.
Some hotels offer a free shuttle to and from the airport. Look for this information on the hotel web site while you're researching rates before your trip.
Some hotels also offer an airport check in service. For example, Harrah's owned properties (Paris, Bally's, Harrah's, Rio Suites, Caesars Palace, Imperial Palace) and the MGM Grand in Las Vegas have a check-in desk at the airport. Find your airport's web site and see if they offer any hotel check in services. This can be a huge time saver.
Some taxi drivers will take advantage of tourists by "long hauling" them, which means they take you by a longer route to your hotel than is necessary. This is another good topic to research in advance of your trip. Use Google maps or Mapquest to see which route from the airport to your hotel is the shortest.
Long hauling is a hot topic among frequent Las Vegas visitors, as taking the freeway (the I-215 connector to I-15) out of McCarran Airport (LAS) to the Las Vegas strip adds four miles to the route, vs. taking Paradise Rd. out of the airport and using surface streets (Paradise, Koval, Tropicana, Las Vegas Blvd., Dean Martin Drive.)
However, sometimes the longer freeway route can be faster than the shorter surface street route. It's up to you to decide which is more important to you, the speed of the ride or the cost of the ride; and to tell the cab driver either to "take the fastest route" or "take the least expensive route."
In conclusion, the briefest and most valuable advice I can offer any traveler is to use the Internet to thoroughly research all aspects of your trip. In addition to researching prices, look for reviews of airlines and hotels that are written by travelers. No airline or hotel points out their flaws on their own web site!