Although sometime the ritual layout might change, the most common one I use is this one with chairs in a circle for small ritual (20 or less people). We hold it either in the fellowship hall or in the outdoor courtyard depending on the season/weather conditions.
When calling corners, the congregants face east and turn clockwise so they finish in north. Then they can be seated and are already facing the altar. When it is time to bid the corners farewell, they can rise and are already facing north. So then we can turn counterclockwise and finish facing east and exit in recessional.
For medium size rituals of 40-60 we might use a similar layout but arrange chairs in two banks with a center aisle. When congregants step forward for cake and ale, they come down the middle in two lines, then turn to their team and walk around the outside to return to their seats from the back so traffic flows smoothly in two opposite moving circles. The corner persons also serve as cake and ale people and stand in on either side of the spirt altar when it is time. Two of them serve the counter clockwise circle. The other two serve the clockwise circle.
For larger ritual (up to 200) we use the main UU sanctuary building rather than the UU fellowship hall or outdoor courtyard.