If you were planning on backpacking, one of the first things that I would ensure, is that you have a great backpack, something with comfortable straps and many pockets and something that breathes, so that you don't have an incredibly sweaty back all of the time.
Regarding clothes, you will want light clothing, t-shirts and shorts mainly, but with a pair of jeans and one light jumper, a thin coat which is waterproof might be useful, swimming costume of some type might also be good, a nice shirt and trousers/blouse and trousers/skirt for a nice evening and a pair of good walking shoes/boots. You will want light cotton undies and thick socks and possibly a thong/flip flop/teva style shoe.
You will need towels, wash bag with toiletries etc.
You might also want a water bottle, salt tablets for potential dehydration, sun cream, after sun, a small first aid kit with plasters. You might want a swiss army style knife, definitely sun glasses.
Since you might want to travel through hostels, take a sheet, a pillow case and some bug cream.
Regarding clothes, you will want light clothing, t-shirts and shorts mainly, but with a pair of jeans and one light jumper, a thin coat which is waterproof might be useful, swimming costume of some type might also be good, a nice shirt and trousers/blouse and trousers/skirt for a nice evening and a pair of good walking shoes/boots. You will want light cotton undies and thick socks and possibly a thong/flip flop/teva style shoe.
You will need towels, wash bag with toiletries etc.
You might also want a water bottle, salt tablets for potential dehydration, sun cream, after sun, a small first aid kit with plasters. You might want a swiss army style knife, definitely sun glasses.
Since you might want to travel through hostels, take a sheet, a pillow case and some bug cream.