When laying out a sprinkler system, there are a few things to keep in mind. One, you need to cover the most area with your sprinkler heads as possible without overspray onto unnecessary places (sidewalks, patios, etc). Two, to get proper even converage of your lawn area with your sprinkler head placements. You will need a combination of sprinkler heads to do this, from 45° nozzles to full 360° nozzles. Below is an illustration of a typical sprinkler layout. Notice the use of half circle nozzles, full circle nozzles and quarter circle nozzles.