Getting a degree approved

I’m afraid you cannot post it to the embassy. You may need to go there in person or find someone else to go there and do it for you.

I had to do this for my son early this year.
The degree has to authenticated by an official notary and then sent off to the foreign office to be approved and then off to the Chinese embassy. It is a lengthy process which you can take upon yourself but my advice would be to pay a notary to do it all for you. It doesn't cost an awful lot more than getting all these procedures done yourself (by either visiting these offices or sending by registered delivery) and saves you a lot of hassle.