Believe me up until now, I am still perfecting to make my own chapatti's shape to be round or circle. Most of the time, I ended up on elongated or something like an alien ship or flying saucer that came from outer space. Seriously I don't watch my in-laws to make it since I am thousands of miles away from them, so I just learned it on my own by watching it on youtube.
Again you don't have to be an expert to cook something. Cooking should be a passion. You should love what you are doing so that it mirrors what you prepare before you serve it to your family and beloved.
Chapatti is made out of wheat flour. I haven't seen anyone mix it with white flour. Just to make a sample chapatti, use two cups of wheat flour and then only 3/4 cups of water and put it in a mixer to make a dough. Keep the dough in an open container for 20 minutes before you roll it into balls which is only a coin size.
Just use a thick rolling pin to make the size more round. Use a tava or a non stick pan and don't use any oil. Once you preheat your tava or non stick pan place your rolled dough and once you see small bubbles coming in, just roll your wheat dough and press it using any clean cloth to make the chapatti balloon in size.
Spread some ghee or butter in a ready hot chapatti and keep it on a tiffin to maintain it's temperature. Chappati is always part of Indian dishes which is always good to compare with any curry recipes.