1. Don't take more than you need too! Seriously, you will be there wanting to buy something and be thinking damn, I really didn't need to bring the kitchen sink with me after all. It's dang heavy to carry, it takes up all of your shopping space, and it weighs a tone, that could be on all these neato things from
2. Wear sunscreen. Remember that song from the Class if 1999? They had it right. Sunscreen is awesome. And plus it keeps your skin nice and wrinkle free, and stops sunspots and skin cancer and that stuff. So trust me. On the sunscreen.
3. Take some small zip-lock clear plastic bags. You may not need them, but if you are caring liquids or gells (under 100mls) on your carry on you will need them. You can normally get them at airports, but I have seen some places charge for them, and they can come in pretty handy for things like toothbrushes, wet clothes, broken jewelery and all sorts of things that you'd otherwise be thinking "Man I really wish I had a ziplock bag right now.
4. Take Ear plugs and an Eye patch! I used these almost every night when we where traveling! It is akwards to throw something at someone you don't know who is snoring while staying in a hostel or backpackers. And alot of hotel's have very thin walls and you can hear people nextdoor and on the street.
5. Take a book or a magazine and an MP3 player. At some stage you will be waiting for a plane or a bus, or a boat, or a train and it is good to have something to entertain yourself with. I would recommend not taking something fancy like an ipod, just take something cheap and replaceable just incase you loose it, or someone decideds it is shiney and wants it for themself.
6. On that note, be careful and have your wits about you. You probably won't get pick pocketed, but you might. When you are in busy places, keep and eye out, be weary of anyone that approaches you. If they keep talking to you when you have said that you can't help, or are not interested or don't have a lighter, look around you. They often work in teams' one person will try to distract you while the other will pick your pockets.
Also there are bag slashers that will cut a whole in your bag nic your wallet and be gone. I haven't had it happen anywhere while I was traveling, but I have had it happen about 30seconds from my door when I lived in the centre of London. (admitidly I did look like a tourest cos we were carring bags and suitcases just returning from a holiday. "Can I borrow I lighter?" "I don't have one" "Can I just borrow a lighter?" "Um no, I don't have one" he just kept going on = DING DING DING DING DING!) I realised what was happening and whipped around just as some guy was pulling his hand out of my pocket. I hadn't felt a thing and he would have gotten away with it, if I had not realised something was up and turned around. Luckily for me, and unluckily for him I only had a handful of snoty tissues in my pocket because I had a cold. Ha Ha! In your face you pocket picking arse!)
Also I would not recomment taking anything valuble or specail to you, be it jewelery or anything else. Even in backpackers people can take things from right out of your drom. It normally doesn't happen often, but it does happen. I had a jacket stolen once. Not happy.
7. Take your own food as much as you can. You will save so much money! There will be food anywhere close to a big tourist attraction, but it is hard to find a cheep place and often the food is pretty rubbish. It is nice to eat out while you are away every now and then, but it is a good way to spend all of your money and often the food is not fantastic, because it is aimed at tourists that will only go there once and never come back. If you really want to eat out, get a Lonley Planit and check out the recomndations. You can trust them. Other than that, I recommend finding a supermakert (and in some places even they are not cheap) and buying a few things for a packed lunch or to at least take along to snack on. You will save a bundle!
8. Take a tourch. Them things come in mighty handy! The headlamps that campers use might look a little silly, but they are even handeir still because well.... you can use your hand! Both of them! (asuming you have two) and besides, no one can see you looking silly because it is dark. If you come home late, and there are people asleep in your dorm don't be a dick and turn on the main light, whip out your little torch :)
9. Take a padlock. If you can't put your things in a locker then you can at least put in around the zips on your luggage. Most backpackers or hostels will have lockers, sometimes you will have to buy or hire a key from them, so it is cheaper to just have one with you.
10. Take a scarf. If you are going sight seeing, often that will be going to some of the breathtaking chruches or mosques. It doesn't matter if it is not something you believe in. It is a holly place and you should respect them. If they have signs up saying don't take photos, Don't take photos. If they have signs up saying no talking, don't talking. Even if there is not a sign up saying to cover your head or shoulders do it anyway. It is respectful. I have seen people cueing up to get into St Pauls Basilica for 2 hours, only to get turned away at the door because they were not covered. It doesn't matter if you don't believe in it, it's about experiencing a piece of history or culture of where you are right then and there. Even if it means nothing to you, there are probably a lot of people that have pilgrimaged from all over the world to get there to see that, so show a little respect.
11. Take a camera! I'm guessing you are already planning to take one, but take along spare batteries and spare memery card as well. And a charger. Also, as much as it is good to have your big camera that takes amazing photos (and I took mine everwhere) it is really handy to have a small one as well. They are easy to carry, don't take up much space or get in the way, and you can get them out easy peasy to take a photo without any fuss.
12. Check out the plugs in the country you are going to, and take a plug adaptor. A universal one is a good idea because you can use them most places.
13.Don't buy the first thing you see! If it is right next to a train station, or an underground station, or right next to a big attraction, you will almost certainly find it cheaper somewhere else. Probably right around the corner.
We got out of the tube and saw a fella selling sunbralla's in Rome. He was selling them for 8euros. We said we'd take one for 5. He said ok. My, my, aren't we cleaver! We walked around the corner and saw a stand selling them for 3. D'oh!
14. Buy a Lonely Planit of the place you are going. They are full of wonderful tips, bits of informations, recommandations, lingo. They are heavy though. We meet one chick that would rip out the the pages of the places she was in and carrie that round with her. What a brilliant idea! It gets heavy carring everything with you. Lonely Planits come out every year so it doesn't matter if you rip out the pages, because in a year there will be out of date anyway. Then if you want to be a nice person, when you leave you can give them to someone else.
15. When in Rome... Don't buy water. Ok well buy the water once so that you have a water bottle, but don't buy any more after that! The Romans are very proud of their water. You will see water spots all over the place where you can fill up your bottle for free and the water is perfectly fine to drink. It tastes good, its cold, and its free! Yay!
16. Print out confirmation of all of your bookings. Something may happen where you get to a hotel or backpacker or airport and they can't seem to find your booking, or don't have a space, or the price has gone up. If you have a print out of confermations from them, they can't wiggle their way around you. It never happend to us, but I have heard of it happening to others. We took a print out of every single place we went, just incase. It is better to be safe than sorry!
17. Take a notebook, and write down all of the numbers of hotels, or busses, or anything you think might be handy. Just incause it's not as easy to find where you wanted to be and you need to call up for directions. People are normally really helpful and can tell you how to get where you need to be. Also have things written down on paper incause your phone goes dead and you need a payphone.
18. Print out a copy of your passport and leave it with someone back home that you know you will be able to get in contact with.
19.2 Oo while I remember, it is a brilliant, brilliant idea to take a little mini first aid kit too. If you are only having carry-on then you won't be able to take scissors or anything, but take some plasters or band-aid's, insect repallent, insect bite cream (No matter how much I spray myself with no-bitie stuff, I still get bitten) sunscreen, (aftersun is good to sometimes incause you forget sunscreen), Ginger pills if you get travel sick, Imodium! You probably won't get food poisening, but sometimes just eating food you are not used to can upset your body a bit.
20. Have a totally amazing time! You will go to so many amazing places and see some amazing things! Have fun, be possative, and look at the bright side of things. Even if something awful and unforseen happen's - it may seem like a disaster, but you will have a great story to tell when you get back, and the older you get the funnier it will seem!