1
Always leave some extra room in your suitcase, even if you are traveling on official duty. You'll never know when you'll need to buy something exotic or rare.
2
When taking a connecting flight, always try to take the same airline. Otherwise, it will be your loss if you end up missing your second flight bacause of a delay.
3
Always remember to take photos when travelling. Memories are important and you'll always cherish them later.
4
Double-check your your stuff after packig, especially important things and necessities like contact lens solutions, credit card, passport, tickets, medications etc.
5
Try to avoid unpacking your entire luggage at a hotel, especially if you are staying for just a few days. Take out only the things you required.
6
Don't forget your mobile phone charger! it is perhaps one of the eaiest things to forget, and has spoilt a vacation for many people.