I have just been offered a place to study in nankai university. Need details of student visa.

For student visa application, you need to provide passport valid for more than 6 months, photo and application form V2011A and form V2011B. Besides, you need to provide the original JW202 Form issued by the relevant Chinese Government or authorized departments; the original Admission Notice from Nankai University with the seal and signature and A Physical Examination Record for Foreigners.
BTW, if you will be sponsored by someone, the original guarantee letter from your sponsor in Nigeria and original recommendation letter from two experts and certificate of graduation are required.