A first trip abroad goes wrong in administrative ways rather than dramatic ones. The flight is easy. What catches people is a passport rule they had not heard of, a card that stops working, and an insurance policy that excludes exactly what happened.
The passport six-month rule
Many countries require at least six months of validity remaining beyond your entry date. Some require three. A few only require validity for the stay.
The important part: airlines enforce this at check-in, because they are fined for carrying someone who gets refused entry. So a passport that is legally valid for another four months can prevent you boarding a flight you have paid for.
Check your destination's specific rule when you book, not when you pack. Renewals take weeks and longer in peak periods.
Insurance: read the exclusions, not the summary
The headline benefits are all similar. The exclusions are where policies differ and where people discover they were uninsured.
The three that catch travellers most often:
Motorbike and scooter riding, excluded unless you hold a licence valid for that engine size in your home country. This is the single most common uninsured claim in Southeast Asia and southern Europe.
Adventure activities — skiing, diving beyond a certain depth, trekking above a certain altitude — usually requiring a paid add-on.
Pre-existing medical conditions, which must be declared. An undeclared condition can void the medical cover entirely, including for unrelated events at some insurers.
What actually matters in a policy is medical treatment and repatriation. A cancelled flight costs hundreds; a medical evacuation costs tens of thousands.
Money
Carry two cards from different providers, stored separately. One blocked or swallowed card should not end your access to money.
Always choose to be charged in the local currency. When a card machine or ATM offers to bill you in your home currency — dynamic currency conversion — the exchange rate is set by the terminal operator and is consistently poor. Decline it every time.
Set a travel notice if your bank's app offers one. Many no longer need it; many still block anomalous foreign transactions anyway.
Some cash on arrival. Not much, but a taxi or a bus from an airport at 1am is not always a card transaction.
Proof of onward travel
Airlines frequently ask for evidence you will leave the country, because immigration can refuse entry without it. One-way travellers get caught at check-in by this regularly.
A return ticket, an onward flight, or a bus or train booking out of the country all satisfy it. If your plans are genuinely open, a cheap refundable onward ticket is the standard solution.
Documents
Photograph your passport, insurance policy, and any visas, and store the images somewhere reachable without your phone — an email to yourself works. Keep one paper copy in a different bag from the original.
Note the local emergency number, and your embassy's location. In Europe, 112 works everywhere.
Two habits that prevent most problems
Arrive in daylight on your first day in a new country. A night arrival in an unfamiliar city, tired, without local currency, is when people get overcharged and disoriented. It costs nothing to prefer an earlier flight.
Book the first two nights, not the whole trip. Enough structure to land safely, enough flexibility that the rest of the trip responds to what you actually find.
What to worry less about
Packing. Almost everything is buyable at the destination, usually more cheaply. Beginners over-pack for contingencies and under-plan for admin, when the admin is what actually goes wrong.