• 2 T-shirts
• 1 vest (to avoid where locals could find it indecent)
• 1 T-shirt with long sleeves
• 2 pairs of trousers (1 light and 1 warmer) with a zip part below the knee and/or around the thigh area (short)
• [For girls: 1 long dress or skirt with a zip part below the knees - 2 in 1]
• Light fleece
• Light waterproof jacket
• Sarong (to buy there) or even better a fairly warm shawl to share on the (absolutely freezing!) air-con bus
• Bandana (multi-purposes)
• Underwears x3
• Socks x3
• Bikini/swimming trunk
• Sandals
• Low-cut hiking boots
• HAT!

The idea is to take as little as possible and buy and discard along the way. For instance in the Himalayas we'll have to buy warmer clothes but only for a relatively short period of time - there is no need to carry them before or after - and we'll give them away to somebody who needs them once we reach a warmer climate.

Accessories:

• Silk sleeping sheets (1 double and 1 single if we get separated in dormitories) - absolute essentials: you DO NOT need a sleeping bag except on expeditions, and again you can buy a cheap one then and give it away to somebody who needs it afterwards
• Fast-dry towels (in nice tiny bags from Nomad Travel to store all the hygiene/beauty products together)
• Ziplock bags or other waterproof bags
• Shoulder bag (one per person) - to be used as day bags
• Alarm
• Maglite or equivalent - and/or headlamp(s) to go hiking at sunset/sunrise
• Money belt(s)
• Camera(s)
• Very light/compact mirror
• Rechargeable batteries and charger - you don't want to be polluting the gorgeous countries you visit by using single-use batteries!
• Sink plug
• Washing line
• String
• Whistle
• Earplugs
• Sewing kit
• Last but not least: Duck tape!

And you don't want to get bored during this 24 hours bus-ride...

• Games (apart from the obvious playing cards we're taking a couple of magnetic games for travel: snakes & ladders, chinese checkers - my favorite - and chess)
• Personal travel journal and the pen that goes with it
• Books (the essential bit and we're not talking guide books only)

Other little extras:

• Pictures of family and friends to show to other travellers and local people
• Little presents to give to people (London postcards and other European souvenirs easy to transport with you in large quantity)