Wire directly from your bank is the best option. International wire cannot be done online, you need to fill out a form, which is typically available on your bank's website, then bring it to a branch, or fax over. The form should have all the information you need. Typically you need the correspondent bank information, that is, the intermediate bank that the Chinese bank has an account with. This is usually a large global bank like Chase, Citi, BOA. Go to the Chinese bank's website to get all the information. Western Union is way too expensive.