The first one or two dosas will tell you if your batter is of right consistency.
Heat a seasoned tava / nonstick flat pan. Once the pan is heated then keep the flame medium.
Spread a little oil on the tava. Stir the batter and pour a ladleful of batter on the tava, in a thin layer. Or pour a ladleful in the center on the pan and spread it in a circle with the back of your ladle, as you do for dosa.
The dosa will form holes all over as it starts cooking. Let the dosa cook uncovered (if you like it a little crisp), or cover it if you like it soft. It will start to brown at the bottom, which will be visible at the edges of the holes.
By the time the dosa is lightly brown at the bottom, which will take about a minute, the top of the dosa will also be cooked, (it will change color from pure white to dull white).
Flip it with a spatula and cook on the other side for a few seconds.
Take out on a plate and serve immediately. Ragi dosa needs to be served hot.
Make all the dosas in the same way. Remember to stir the batter every time you take out a ladleful of batter as the rice flour tends to sit at the bottom.