This a guide if you start from Metro Manila. This is all according to my experience. I have a brother who lives in Manggahan Cavite. He would invite me sometimes to visit him.
EDSA. There are a number of air conditioned buses that ply along EDSA.
Taft Avenue. Starting at Lawton, near the Manila City Hall.
Baclaran. But the buses there might already half full or almost filled. So it’s not a good idea if you take a bus from there.