These suggestions will take you through my general planning process and the steps to go through until that final moment when you are at the airport and can finally exhale. What's done is done. You're on your way.
Book Your FlightYou've already looked at airfare and made the decision to go, you may as well solidify it. Book that baby!
ResearchThere are quite a few different aspects of a trip that you can research online before you go. I have gone on trips where I research the heck out of it before I go and ones where I can't be bothered to open the guidebook until I'm on the plane. I have to say that I have liked both equally. And now with WiFi pretty much everywhere, you can always search online for tips as you go.
But for your first trip I recommend getting your ducks in a row ahead of time. Also, I prefer to book accommodation as I go, but if you prefer to book your hotels ahead of time, you definitely need to do this research early on.
There are so many good resources online. Try to steer clear of marketing hype and look at real traveler experiences like on Leslie's Travel Snacks (he he)! You can join Facebook travel groups, look online at TripAdvisor, read travel forums like Lonely Planet Thorntree, and get guidebooks (Lonely Planet) either online or from your library (yes, libraries still exist and they have old-school paper books ;) ).
Local Food- Look up common street food. It's easier if you can recognize a few dishes by name or sight. Learn which ones you think you'll like, and which ones you want to steer clear of. Not into trying sheep balls just yet? Take note of that dish LOL. If you're vegetarian, see if there are any vegetarian options or any specifics to look out for like dishes that might seem vegetarian but are made with meat stock.
Attractions- This includes not only major sites, but "secret" traveler recommendations and also celebrations and events. Having an idea of what you want to see, any timing limitations (the museum is only open on Saturdays or the parade is on the 15th) will help you have a general roadmap of how you want to move through the country.
Transportation- Every country's public transportation is different. Some use shared vans, old school buses, or taxis. You should learn what to expect, how to use them, and basic cost.
Phrases- Learn how to say in the local language "hello", "thank you", "excuse me", "vegetarian" (if you are), and anything else that's important to you like "no spicy" or "toilet". See each country for some useful local phrases.
Customs- It's like being responsible for knowing the laws where you're visiting. Knowing the local customs will help you fit in, make you a a better traveler, and help avoid travel faux pas. In some countries, pointing, eating with your left hand, or even sitting the wrong way are big no-nos!
Scams & Safety- Don't stress too much about this but know some basics like if there are areas not to go to after dark or common scams. (see Common Travel Scams to Watch Out For)
Money- Get a general feel for the conversion rate. Write down $1 = x in local currency and 1 in local currency = $x so you can make quick calculations in your head. ATMs are pretty common these days but make sure they are at the airport and in the main areas you want to visit.
Electricity- You'll want to bring any necessary electrical adapters (this just adapts the shape of the plug, not the voltage). If you are going places that will require more than one adapter, consider a universal adapter. You shouldn't need a converter unless you're bringing something like a hair flattener.
Gather Your GearIf this is your first trip, you will be buying a few essential backpacking goodies, starting with a good backpack. The Osprey Fairview is the best on the market at the moment. It's not too big, is high quality, has good features, and has a zip-away suspension.
Check my packing list for suggestions on what to pack. You'll definitely want a laundry line, sink stopper, good backpack, flashlight, first aid kit, a travel towel, and luggage locks.
Read my packing tips and get your wardrobe together for your trip. It's better not to wait until the last minute in case you need to buy a few extra items to complete the perfect set of clothing.
If you bought new shoes for the trip. start wearing them in ASAP. Blisters and travel are no bueno. Especially when you only have one pair of shoes!
Logistics to Take Care of Before You GoBefore you do anything else, check the visa requirements for the country you're going to. This includes what it might cost you, if you can get it on arrival or if you have to apply for it in your home country before you depart, and how long you will be allowed to stay. There also might be requirements on your passport like having a certain number of blank pages or having at least 6 months before it expires.
Do you need to arrange for someone to watch your house or pets? Have your mail held and deliveries suspended while you're gone or ask a neighbor to take those in for you.
No matter how much pre-trip research you do or don't do, always know how to take local transportation to your hotel when you land and how much it should cost. Have a printout of your hotel reservation (in the local language if possible). This will make it so much easier to ask people (airport info desk, taxi driver, bus helper) to help you find your hotel.
Make sure you know where your passport is and that it's not expiring soon.
You need to determine how you will be paying for things as you go. I personally prefer using ATMs. Not every place takes credit cards and you can incur foreign transaction fees using your card abroad. Double check that there are ATMs at the airport and that they are usually open and functioning. See Getting Money During Travel.
By now you should know about how much the trip should cost you. If using a bank card to get your money, move almost all of the money out of that account other than what you'll need. This is just extra protection in case your card is compromised.
Figure out what you're going to do about your phone (if you need phone service or data or if WiFi will suffice). (See Using Your Phone While Travelling Internationally)
Lastly, be sure to follow my Pre-Departure Travel Checklist!
Now pack your bag and get outta there! Soon you'll be in the seat of the plane and on your way!