South African Living In Hong Kong - want to travel to China

Hello, I am a South African on a work visa in Hong Kong, with a Hong Kong i.d. I would like to visit China later this year, and would like to know how to apply from Hong Kong for a Chinese visa (preferably a multi-entry one year visa, so that I can travel a few times over the next year).

Thanks so much.

Vanessa, South African in Hong Kong