You should have the below documents provided by your cousin:
(1) Invitation letter from your cousin
(2) passport copy of your cousin
(3) Copy of Chinese visa page and residence permit of your inviter's passport
you need to prepare the folowing documents in person:
(I) Original passport with validity more than six months and minimum 2 blank visa pages;

(II) Photocopy of the first 2 pages (personal information) of the passport and the recent Chinese visa page if there is any;

(III) One fully completed visa application form in Chinese or English, attached with one of the applicant's recent color photograph (30mm X 40mm)

(IV) Certificate of the relationship between you and the person in China you want to visit (original and photocopy)