Top tips for clever backpack packing

You've planned your destinations, booked your ticket and quit your job to set off on the adventure of a lifetime. As D-day approaches you start the task of whittling down your earthly belongings to fit into just one bag  - and one light enough for you to haul around over sandy beaches, ropey swing bridges and up hills.
Two words: pack wisely...
You’ve probably never needed to reduce your material possessions down to what you can carry (which can actually be liberating – but you don't want to be on the other side of the world finding you are missing essentials and have stocked up on useless items. So here's a guide to some of the things I have found invaluable over my 3 years of backpacking:

Bag choice

Firstly, unless you’re uniquely visiting big cities or setting sail on a cruise, I would strongly recommend a backpack over a suitcase. You'll need one with comfy straps (as I’m sure you will be lugging your bag around with sun-burnt back and shoulders at some point!). Next, choose one with a few compartments, so you can find your things without having to search through the whole bag. An invaluable feature I have found is having a backpack which fully folds open as opposed to just opening at the top. This lets you fish out the stuff at the bottom with ease and stops you needing to wear the same clothes day after day.
Top packing tip: roll your clothes instead of folding; saves space and easier to see everything.

Gadgets

Filter water bottle: I’ve recently discovered these and I believe every traveller should invest in one. Most countries you will visit will not have the infrastructure to recycle plastic water bottles and you don't want to be adding to a nation’s rubbish problem. These water bottles allow you to fill up from a tap and filter the water so you can drink away. You'll save money in the long run and can feel slightly smug about not getting through multiple plastic bottles a day.
Wind up or head Torch: I'm a fan of my wind up torch as it will never die, but a head torch is super handy for hands-free searching in the dark. If you find yourself in villages where the electricity is not on 24hrs a day – you can do a quick survey of the toilet before committing yourself in the darkness!
Bag lock: handy for an extra bit of security.
Universal adapter: essential for charging your gadgets en route – you can universal travel adaptors that convert every country to every country which save space.

Kindle/tablet vs book: I’ve not yet been converted to the Kindle or the idea of downloading books as I love the actual ‘feel’ of a book. Loads of travellers I meet swear by them because you can download countless good books and you're not limited to your luck in finding a gem of a book in the swap shops. The downside is being limited by battery life, and any gadget is an additional draw for would-be thieves especially, at the beach and on buses.
Underwater camera: these are great as they can survive the knocks and drops of travelling, they cope with sand well, can be dropped in water and they still work. Mine has allowed me to snap away whilst jumping off waterfalls, snorkelling, tubing, caving, sand boarding and skiing - capturing the most active moments of each trip.
Wireless radio iPod tuner/transmitter: an ideal gadget for campervan road trips in Australia, New Zealand and wherever you don't have good radio signal- they cost peanuts and allow you to broadcast your iPod tunes over short wave radio for the car stereo to pick up and play through the speaker system.
SD card reader: another small and ingenious gadgets for you to transfer your photos direct from your camera’s memory card to a computer (and you can get card readers for tablets now too). You can quickly back up your photographic memories and a card reader takes up less space than a big cable.
Travel towel: one to buy before you go. These are highly absorbent, lightweight and very compact. Just don't do like me and leave your in your hostel room in Singapore on your 2nd night of your round the world trip.

Silk sleeping bag liner these can be bought online and I have used mine loads. If you're on a budget you will surely come across many a suspect bed linen. You can lay this on top or get inside to avoid the dodgy stains. Being silk it will keep you cool. Last night I used mine as there were a few cockroaches running around my hut so I cocooned myself in mine to the jealousy of my travel partner

Clothes

As you are only taking a limited wardrobe here's a few things to consider: ditch the high heels, glitzy dresses and countless white clothes. You'll probably find that casual cotton clothes will be the most used. Having met girls on the road who have giant bags full of high heels and numerous pairs of shoes, they have all regretted it. White things will get dusty/sweaty and grubby so to avoid too many laundry runs have some other colours in your bag.
One thing I have fallen victim to, is packing too many items of the same colour (I am currently in Central America and have far too many turquoise green items; two pairs of green shorts, two green tops, green dresses etc so if I wear these items together I look like I am trying to camouflage!) I also have a tendency to pack lots of patterned/coloured clothes which don't go with my other patterned things, so take a bit of time to make sure you have items that go with lots of other clothes in your backpack and to avoid looking like a colour kaleidoscope.
Hiking boots/trainers if you are planning on doing a lot of treks, and are a serious hiker you may well want to take a pair of hiking boots. I personally have done many a hike in jungles with only a shoddy pair of converse. Apart from this a pair of sandals/flip flops will be essential, until you lose them on the beach one evening and you'll have to replace. On my first round the world trip I got through about 25 pairs of flip flops.
Swimwear will become your new best friend; you'll probably find you'll ditch wearing undies in favour of your cozzie. Also take note of where you're going especially when visiting cultures that are more modest in their dress code. You’ll often need to cover head, shoulders and knees when visiting religious temples so pack some clothes for these situations and be sure not to offend. You’ll inevitably buy new clothes on the road, so leave room for clothes and souvenirs!

Other necessary bits and bobs

Toiletries - you won't need as much as you think and shampoo, conditioner, after sun, sunscreen, shower gel, toothpaste can all be bought around the world and often more cheaply than at home. If you have a particular essential item, take it, but you will probably appreciate the ‘less is more’ idea. Tiger balm is a 'cure all' essential so be sure to pick some up in South East Asia if passing through.
Medicines – again, unless you take specific medication, the basics will do as pharmacies can be found the world over. Also the miming of ailments in a far flung pharmacy is part of the experience of travelling and leads to many a funny travel tale!
Games - these are 'non-essential' but in my mind are the things you regret culling from your back pack. Often games will intrigue locals, providing spontaneous moments teaching kids new games, making friends with other travellers and meeting other like-minded people. I always take my fire and practice Poi as I quickly get bored on beaches. Also my snorkel and mask are always with me, so I can check out the fish wherever I am. Other great games include: a deck of cards (ideal for delayed travel situations) travel chess, juggling balls, travel hula hoop, devil sticks, travel staff, Dice for Yahtzee etc.

Remember pack light, leave room for things you pick up along the way and enjoy the freedom of having only a few possessions. We don't need half the material objects we’re led to believe, so enjoy living with your life on your back! Above all don’t forget to take your sense of adventure!