How to Pack a BackPack for a Long Journey

After backpacking around Asia and Australia for nearly a year we think we've discovered the best possible way of packing enough clothes to keep you clean until you find a laundrette (or stream).
The key is to go about it systematically, use the design of the back pack to help your packing decisions i.e do not put an umbrella in the bottom compartment that is meant for shoes, put the shoes in there…

The Bacpack Essentials:
Poncho / Pac a mac: You haven’t seen rain until you have seen tropical rain, you might look a bit silly, but this essential bit of kit will keep you and your possesions dry.
Insect Repellant: You’ll be patting yourself on the back for bringing this as soon as the sun goes down, the stronger the deet content the better, but be warned any more than 60% deet can start to irritate the skin.
Universal plug: You’d be surprised how many places we came across that didn’t have any plugs in the sinks or baths, and if your living on a budget you need them to wash your clothes!
Travel Towel: This is the best piece of kit you can buy! The microfibre towels compacts down to a small package, dries quicker than normal towels, is anti-bacterial and can dries at least two people.
Linen/Outdoor Trousers: DO NOT TAKE JEANS – they don’t fold well, take a lifetime to dry and shrink when they are washed, take linen or lightweight outdoor trousers, they will keep you cool and fold up remarkably small.
Penknife and Scotch/Gaffa tape: There are things that can do almost anything, these two items are on that list. If you have a penknife and scotch tape you can make or fix anything.
Walking Shoes: Not the most attractive shoes, but they will go through anything and offer ankle support when hiking.

Packing:
When it comes to packing there is one rule that I have, which is: ROLL, DO NOT FOLD! You’ll save plenty of space by using this technique, however if you need to save more space then I recommend using vacuum bags. They are lifesavers, and they actually work, compressing the clothes by at least half. I packed my bag so I had this lining the inside of the back pack, then I stuffed everything else into the middle of it, that way the things in the middle are not only waterproof, but they are also protected against any knocks during travel.
Make sure you have your travel documents with you at all times, but do keep a copy of them inside your pack.
So next time your thinking about flights to Miami to travel the Gulf, remember these tips and there won't be much that can surprise you.