You don't become a travel expert by reading, researching or planning. You become an expert by experiencing travel - getting out on the road, seeing the world with new eyes, making mistakes and learning to laugh them off. This approach will serve you better than any roadmap or set of instructions.
Nevertheless, there are a few things I wish I had known when first venturing out into the world. If I could start over now, what would I do differently? Here's my list.
Pack fewer clothes and more money. After struggling to stuff extra clothes into my small carry-on, I learned that I could easily buy solid colour T-shirts that can be layered as needed almost anywhere. Often, it's easier to find a new shirt than to wash an old one. Sometimes it's cheaper, too.
Money, however, shouldn't be spared when packing for a trip. Whatever you expect to spend along the way, take double the amount. After visiting more than 150 countries, I recently made the mistake of not having enough cash to pay for an entry visa into Comoros. It was stressful and entirely unnecessary. Bring more money; you can always redeposit it when you get home if it proves unnecessary.
Keep your receipts. When exchanging money, hang on to the receipt until you've left the country. Once in a while, someone at the airport will want to see proof of all your foreign exchanges. Not being able to show proof is grounds for a fine. Usually, though, this harassment can be resisted. In Angola, they take this to the limit by asking departing travellers to show their wallet for inspection before clearing immigration. (Tip: don't use a wallet in Angola.)
Taxi drivers can be friends or enemies. Most taxi drivers are honest and can help you with all sorts of problems. If you find yourself in an uncertain situation and aren't sure where to turn, ask a driver. Others, however, will drive you in circles in an attempt to ratchet up the fare. Some will lie about knowing your destination just to get you in the car, then drive around asking numerous other drivers at traffic stops until you get on the right road.
The universal rule of taxi haggling for both driver and passenger is that, once both sides agree on a non-metered fare before setting off, neither side can reopen negotiations once you're en route. After the journey has started, you should not try to get a better deal nor should you accept any increase in the fare from the driver.
All airline rules are flexible, no matter what you're told. Persistence and friendliness go a long way. If you're in a situation where you need something changed, ask anyone you can find. Try to get someone on your side - make a friend and they'll often end up pleading your case for you to superiors. In some cases, it's better to call even if you're already at the airport, so keep the airline's phone number stored in your phone in case of problems.
Learn about travel hacking sooner rather than later. A high percentage of business and first-class travellers on many flights are using awards tickets or have been upgraded from economy. Flying in premium cabins can help you in more ways than just being comfortable on long flights, because the tickets can almost always be changed or refunded without penalty. You'll also get to hang out in airline lounges and receive priority treatment - very useful when you need to get in or out of somewhere fast. First class is nice, too, but the difference between first and business is rarely as great as the difference between business and economy.
If stuck, take matters into your own hands. Don't wait for someone else to solve your problem: think ahead. If your flight is cancelled, are there other flights? Is there another airport? How can you get online to look at other options? The first time this happens you may feel terrified, but after a while you'll learn that there's almost always a way out. A good travel disaster - preferably averted at the last-minute, of course - will help you grow in confidence.
Small tips go a long way. You don't have to bribe anyone and you don't always have to tip, but in most parts of the world, even giving something small is appreciated. When in doubt, don't hold back.
Be careful about talking but be open to listening. It's true that you shouldn't openly discuss politics or say anything negative about the country you're visiting. However, just by asking "How are things in ...?" you can usually learn a lot. Inevitably, people will have various complaints and observations. It's helpful to respond to any minor complaints by saying something positive about your impression of the country.
Be flexible ... really. Travellers are often advised to "be flexible", but what does that really mean? Often it comes down to the fact that customs and culture vary considerably around the world. You may hate smoking, for example, but in many parts of the world smoking is still a normal practice. The concept of personal space, something that Westerners tend to value, isn't shared as much in places such as India or Sri Lanka.
Not everything that relates to flexibility is negative, and that's the beauty of travel: you'll inevitably discover things about the outside world that you wish you had with you at home. As you travel, you'll learn your own lessons - but the more important thing is to be willing to go.
Chris Guillebeau, 33, is the author of The Art of Non-Conformity, published by Penguin. He is on a five-year mission to visit every country in the world, and is currently on number 178.