Getting visa to China from another country

Hi, My husband and I are UK residents currently on a round-the-world-trip which will involve going to China in a few months time - we will not be returning to the UK before visiting China so how do we get a visa? we will be visiting Thailand, Cambodia, Laos and Vietnam before going to China - can we get chinese visas at the UK or Chinese embassy in any of these countries? any advice will be greatly appreciated