How to process Visa

Lorry, you can apply for a business M type. The first step is to prepare the required materials including your passport and copy of its data page, the completed application from affixed with a recently-taken passport-style photo, the invitation letter from the conference organizer, and maybe proof of your financial support is required, too. Afterwards, submit your application to the embassy of PRC to apply for it.
In principle, you can apply for it 3 months earlier before your trip, but you are advised to apply for it one month earlier before your trip.