Installing sprinklers in an established landscape requires careful mapping and measuring. Start by drawing an irrigation layout to scale, showing where you plan to place pipes; work around tree roots and hardscaping as much as possible. It’s not necessary to install the whole system at once—you can spread the work out over a few weekends, installing one circuit at a time.

Once your layout is complete, go out into your yard and mark sprinkler head locations with stakes or flags. “Connect” each sprinkler head with paint, chalk, or string wrapped around the stakes or flags to map out pipe locations, including the water supply pipe, control valve locations, and where you’ll need to dig a trench for the wiring between timers and valves.

To make sure your marked lines match your irrigation layout, go back and re-measure the distances between sprinkler heads. Sprinkler heads should be spaced correctly to water each area thoroughly but without wasting water.