I did some backpacking in asia a couple of years ago and will be traveling again through asia and south america soon, it was a life changing experience for me, and I'm really jealous of you. My only advice would be to read up about the areas you intend to see, get some kind of travel guide so that you know what sights you want to see, but stay flexible and go with the flow. You will probably meet people and go to places you never planned too, and that is half the fun
