The Prophet also recommends us to offer obligatory prayers at home, so that our homes are not denied the blessings of prayer. The minimum number of worshipers required for congregation is two, one of whom should be the imam. If there are only two worshipers, the imam stands a little ahead and the other person stands to his right. If there are more than two, then the imam stands on his own and the other worshipers, stand in a row, leaving a distance which is sufficient for them to do their prostration. If one row is complete and a second row is to be formed, it starts at the point exactly behind the imam and worshipers stand to the imam's right and left, in a balanced way.
Every new line starts in the same way, right behind the imam.
But it should have at least two people. If the last line is complete, the next one cannot be started by one person only. In a congregational prayer, the worshipers follow the imam without leaving any gap between his movement and theirs. When he gives the signal for the next movement, all worshipers follow suit.