Turn on the gas and place a idli steamer and pour there 1 glass of water then grease the stand with oil 1st pour a ladle 1/2 orange colour batter, then 2nd layer add white batter and last layer again half ladle green colour and on the middle of it add little onion seeds and steam it for 10 mins on high flame. Turn off the gas and cool it down for 5 mins then unmold the idlis.