Into a thick bottom pan, add water, salt, 1 tsp oil, and bring this to a boil.
Once the water starts boiling, pour the ragi flour to the center of the pan. Leave it as it is for 3-4 minutes. You will see the water simmering and rising over the flour.
At this point, gently make 4-5 holes on the poured ragi flour, to help it get cooked evenly. Cover this with a lid and leave it untouched for 6-8 minutes in low-medium heat.
Now, switch off the stove, and mix the cooked flour thoroughly using a wooden stick or the round bottom of a wooden spatula. (refer notes 1)
Once you have mixed this well, cover a lid and keep it aside for a few minutes, so that it cools down a bit.
When it is warm, transfer this onto a plate and knead well. You can dip your fingers in water to handle the warm dough, but make sure to not make the dough watery.
Keep kneading by further adding a tsp of oil and breaking lumps, if any. This can take 5-8 minutes.
Finally, you should be able to get a soft, lump-free, non-sticky dough. (refer notes 2) Divide this into equal-sized balls and keep them aside.
Dust a ball with some ragi flour and roll it using a rolling pin just like how we roll chapatis.
You may dust more flour if required, but try to avoid it as this can cause the roti to dry up. Be gentle while rolling and do not apply pressure on it as it will be very smooth and can crack easily.
Cover the rest of the balls with a lid while rolling a roti, so that they do not dry up.
Heat a tawa and place a rolled roti carefully. Flip and cook well on both sides. Use a wet napkin to gently press the roti so that it doesn't dry up and to also remove extra flour used for dusting. Alternatively, you can cook it on direct flame.
You may apply some ghee or oil in between, which is completely optional. Once you see that the color of the roti has changed slightly, it is done. Do not wait for it to turn dark as this can slightly harden the roti. Immediately, put it into a hot box or place it on a plate covered with a lid, so that it stays soft for hours.
Continue to roll the rest of the balls into roti and cook them all similarly.