I am a Jamaican. Went to China before on business, how to apply for a second entry and the cost

Fiona, if you still go there for business purpose, you should first prepare your passport and its copy, the application form, a passport-sized color photo, and an invitation letter from your business partner, as well as an introduction letter from your company.
And then submit the application to the embassy of PRC to apply for it. It will cost J$5400.