Technologic said...
Just a school bag of clothes? I feel sorry for the bloke next to you on your long flights
Only 2 things you absolutely need to travel:
1. Your passport
2. A credit card - you can always buy clothes wherever you go. Get a couple of sets for next to nothing, wear them to death and buy some more a few weeks down the track.
Good luck! - it's hard enough work to backpack (rewarding though) without dealing with kite gear. My thoughts would be to choose a couple of locations where you would be happy to spend, say, a month at and just dedicate those months to kiting. Then arrange for your gear to be sent back to friends or family in Aus and then shipped on to you when you get nearer your next kiting destination. Some countries offer a "Poste Restant" service where you can have mail and parcels sent to a post office and you collect the mail from them when you arrive.
With respect to hiring equipment. I haven't seen any places that do, although maybe the really busy places like Tarifa in Spain or the Canary Islands might be good for hiring.
Depending on what time of year you start maybe an option is to do something like this: leave Melb, fly to Mauritius with your gear - spend 4-6 weeks there kiting it up then send your gear home. Mauritius is a good hub for Madagascar and Africa. You can also fly on to Europe from there.
Lots of planning for a year of travel!