I perform a swalat in which 1st Rakat I say 100 times surah Ikhlas, and in second 100 times surah Fatiha. So, I want to know that I am suppose to say Bismillah before starting each surah? or just once before I get a start. If in some Nafal I say 10 times or three (different) Surahs, so same will go with that?