1) A person must fix a place for praying. It does not suffice to have a fixed synagogue. One must have a fixed place for praying in the synagogue. (Shulchan Aruch and Mishne Berurah 90)
2) Even one who prays in his house, should have a fixed place for praying. He should choose a place where the household members will not mix him up. There is no need to fix an exact place, as so long as it is within four Amos (about two meters) of the place it is considered the same place. (ibid)
