I am Nigerian, I have residence permit in China. How can I obtain the macao tourist visa?

Godwin, you should first prepare the required documents including copy of your passport, the completed application form, a passport-style photo, hotel booking record, transportation arrangement, your travel itinerary and your residence permit in mainland PRC. And then submit your application to Beijing office of Macau government to apply for it.
In this case, you don’t need to travel back to Nigeria to apply.