sir i need work permit visa how can i apply what is the requirement of documents

Generally applicants should appear in person with required documents, and may answer questions from the visa officer. The documents requried for a China Z visa include the followings:
1. Duly completed Visa Application Form affix one recent color photo (30mm X 40mm);
2. Original passport with a validity of more than 6 months and minimum 2 blank visa pages, and photocopies of the first 2 pages (personal information) of your passport and recent Chinese visas if any;
3. If it is your first visit to China, you should provide your local police character/clearance certificate;
4. Original invitation or confirmation letter (used to be called Visa Notice) from an authorized government organization like the local foreign affairs office, ect. in China;
5. Registration Certificate of Foreign Enterprises Permanent Office in China/Alien Employment License of
the P. R. China/Working Permit by the State Administration of Foreign Experts Affairs, China;
6. Physical Examination Record for Foreigner (to be attested by Ministry of Foreign Affairs Islamabad.);
7. Supporting letter from your organization.