I'm a srilankan nationality how I apply visit visa to Macau what type of a things I have to do ....

Bascially speaking, you can apply it through the Chinese embassy in your country for application and you are suggested to contact them for confirming.
The documents you need to prepare are your valid passport, an application form, a recent taken photo, your bank statement or any other financial document, visiting purpose proof, hotel bookings and round trip tickets for application.