Um, sunscreen. Always wear sunscreen in Australia, even if they tell you it's the dead of winter! Trust me on this one.

If in a Thai Buddhist site, never point your feet at the Buddha and keep your head lower than Buddha images and monks. The feet are considered the lowliest part of the body, and the head's the highest; so, don't show disrespect because of ignorance!

In China, don't be surprised if locals and tourists alike want to take photos with you because you're Western and thus very different from them. Go with the flow and have a sense of humor, and take pictures with the curious strangers :)