Heat an iron tawa or griddle.
In the center, spread some oil. for non stick pan, you need not grease the pan.
the pan has to be medium hot and not very hot. If very hot, the dosa gets too browned or can get burnt with uneven cooking. If the pan is warm, then the dosa does not become soft and the bubbles or holes do not get formed on the dosa. While making these dosas, you can regulate the flame from low to medium.