Well,now you are on Rama IV Road. You can tank a bus number 45 or 46. When you see the Mandarin Hotel,be ready to get off at the next bus stop. Next, cross the street. Wait for bus number 40. When the bus passes Siam Center, be ready to get off at the next bus stop. Walk straight ahead for about 400 meters. You will pass the temple. The Central World plaza is on your left next to the temple. You can't miss it.