South African Visa Application

I have 2 questions:
1. I'm going to China to work as a volunteer for a non-profit.. Flights and accommodation have been booked and paid. What else do I need to submit, because , I'm not employed anymore I'm a full time student, so, I dont have funds in my bank Acc.
2. As a South African, can I apply in Swaziland for the Visa?